III and II BSc- Assignment

                         
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  1. A.ANNINA TEJASWI

    DB;09

    1. Butea monosperma

    It is commonly known as flame of flowers.

    It is a mesophyte, perennial tree.

    Family; Fabaceae

    It is located infront of P.G block in botanical garden.

    2.Dalbergia latifolia

    It is commonly known as Indian Rose wood.

    It is a mesophyte perennial Woody tree

    Family: Fabaceae

    It is located in Botanical Garden in P.G. Block

    3.Pterocarpus santalinus

    It is commonly called as Red sanders

    It is a Mesophyte Perennial Woody Tree

    Family:Fabaceae

    It is located near L.B. Block

    4.Vanda roxiburghii

    It is an Epiphyte

    Family:Orchidaceae

    It is located near Controller of examination Room in Herbal Garden

    5.Bambusa arundinaceae

    It is a perennial Woody tree

    It is used in construction and making Baskets

    Family:Poaceae

    It is located in the botanical Garden in P.G.Block

    6.Santalum album

    It is commonly Known as Sandal wood

    It is a Hemi-Parasitic Plant

    Family:Santalacea

    It is located in Botanical Garden in P.G.Block

    7.Borassus flabellifer

    It is also Toddy Palm,Mesophyte

    Family:Palmae

    It is located infront of Physics Lab in Herbal Garden

    8.Cycas revoluta

    It is also called as Sago Palm,Terrestrial

    Family:Cycadacae

    It is located near Library

    9.Ravenala madagascariensis

    It is commonly called as Travellers palm,Terrestrial

    Family: Gekkonidae

    Located infront of Library

    10.Areca catechu

    It is commonly known as Beetle nut

    Family:Arecaceae

    Located infront of Library

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  2. M.AJAY-DB-7
    1)AZADIRACHTA INDICA- meliaceae family
    2)it is a perennial tree, woody, erect, ramel,cauline, cymose, pedicillate, 5 sepals,petals-5, tricarpellary, monadelphous stamens..
    3) uses- skin diseases, respiratory diseases, intestinal problems etc..

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  4. NAME:A.ANNINA TEJASWI
    ROLL NO:DB-09

    FAMILY:Fabaceae
    * Mesophyte, annual herb
    * Tap root system
    * Aerial, erect, green, herbaceous, branched, hairy, cylindrical, solid.
    * Carnile and ramal broadly elliptic, ovate or obovate, base cuneate to rounded, apex obtuse to rounded, pubescent; stipules c. 4 mm long, ovate-lanceolate, persistent.
    * Br,Ebrl,pedicel, zygomorphic,Flowers solitary, axillary; persistent; bracteoles foliaceous, auricled.
    * Calyx tube 5-7 mm long, pubescent; lobes acuminate. Petals blue or white, clawed; standard 3.5-4.3 cm long, obovate, emarginate; wings oblong, falcate, adnate to keel; keels obovate, incurved.
    * Stamens diadelphous; filaments unequal.
    * Ovary c. 7 mm long, pubescent; style curved, apex dilated. Pods 5-9 x 0.6-0.9 cm, linear, apically beaked. Seeds many, 5-7 mm long.
    **MEDICINAL USES:Part Used— Root/root bark, seeds
    It alleviates swelling and pain. It has haemostatic action hence it is ued in piles specially bleeding piles. Piles are cleaned with the decoction and the paste of whole plant is applied over it. Leaf juice is used as nasal drops in headache. Oil boiled with dhamasa is used for massage in rheumatoi4 arthritis..

    Decoction is used for gargling in stomatitis and for cleaning wounds. It prevents pus formation.

    ReplyDelete
  5. SHUBHAM LUCAS, DB-01

    1.PLANT NAME-Artabotrys odoratissimus, FAMILY- ANNONACEAE
    2.It is a perennial, woody shrub , tap root system , aromatic. leaf-ovate, lanceolate with unicostate, reticulate venation. Inflorescence-solitary, axillary. flower- trimerous , hypogynus,9 tepals arranged in 3 whorls. Fruit- apocarpous.



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    Replies

    1. Embryology is the branch of biology that studies the prenatal development of gametes (sex cells), fertilization, and development of embryos and fetuses. Additionally, embryology encompasses the study of congenital disorders that occur before birth, known as teratology.NB-26

      Delete

    2. Embryology is the branch of biology that studies the prenatal development of gametes (sex cells), fertilization, and development of embryos and fetuses. Additionally, embryology encompasses the study of congenital disorders that occur before birth, known as teratology.NB-26

      Delete
  6. U.Praveen DZ-47
    Plantname:Tridax procumbens
    mesophyte,shrub,perennial,decumbent stem,toothed leaves,head inflorescence,ray floret,pappus,nectar glands,basal placentation,cypsela.

    ReplyDelete
  7. Name:u.Praveen DZ-47
    plant:Tridox procumbens
    mesophyte,shrub,perennial,decumbent stem,toothed leaves,head inflorescence,ray floret,pappus(helps in fruit dispersal),nectar glands at the base of the corolla,basal placentation,cypsela,
    uses:antiviral,antioxidant,antibiotic,wound healing activity,insecticidal,anti inflammatory

    ReplyDelete
  8. M.V.N.SRAVYA:DZ-15
    plant:Euphorbia hirta
    Family:euphorbiaceae
    1)erect,annual herb,panatropical weed,hairy red coluredstem,cauline,ramele,stipulate,petiolate,opposite superposed
    2)axillary cyme,unisexual,pedicellate,white,bracteate,ebractelate,incomplete,
    androecium infinite,hypogynous,axile placentation
    Uses:cure bronchitis,veneral diseases,impotency,diarrhea,mouth ulcers,dandruff

    ReplyDelete
  9. Telugu news portal Brings the Breaking & Latest current Telugu news headlines in online on Politics, Sports news,movie news visit
    Ap latest political news

    ReplyDelete
  10. Submitted to :- Dr.B.Siva Kumari Submitted by :- T.Mohan Sai Charan , DZ-54

    Semester - V

    Botany Paper - V

    Title:- Cell Biology, Genetics and Plant Breeding

    Assignment

    U- 1. Cell Biology

    1)Mesosomes & it's role
    A)Mesosomes are the infoldings of the plasma membrane in a prokaryotic cell into the cytoplasm. It also helps in the binary fisson

    2)Differences Prokaryotic Cell & Eukaryotic Cell
    A)Prokaryotic Cell:
    -Nucleus is undefined and the nuclear material is present all over the cell.Single circular chromosome present.Plasmid is present which contains extra chromosomal genes which is used in R-DNA technology.Genetic material lacks histone proteins.
    Eukaryotic Cell:
    - Nucleus is well defined and the nuclear material is bound by a nuclear membrane.Chromosomal number varies and they are of linear ,Plasmid is absent.Membrane bound organelles like mitochondria, chloroplast and etc are present.Genetic material is associated with histone proteins.

    3) semi-autonomous cell organelles
    A)The mitochondria and chloroplast are known as the semi-autonomous cell organelles in a plant cell because due to their ability to undergo autocatalysis and heterocatalysis.

    4)What is a Plasmid
    A)Plasmid is the extra chromosomal DNA present in a prokaryotic cell which can replicate independently.They are small circular double stranded DNA molecules in bacteria.
    Plasmids play a major role in genetic recombinations in R-DNA technology which are of great use in science, agriculture,medicine and genetics.

    5) Euchromatin and Heterochromatin.
    A) Euchromatin: The portion in the chromosome which takes less stain and active genes are present and they take part in transcription due to their loose packing.

    Heterochromatin:. The portion in the chromosome which takes up staining darkly and inactive genes are present.This is due to methylation of the chromatin material and high coiling.


    T.Mohan Sai Charan
    DZ - 54

    ReplyDelete
    Replies
    1. DEAR SAI CHARAN,

      GOOD, BUT NEXT TIME PUBLISH IN A PROPER WAY.

      WRITE THE FULL QUESTION

      Delete
  11. U-2 . Genetic Material

    6)Watson and Crick.
    A) Watson and Crick proposed the double helical structure of DNA molecule for which they received a Noble Prize in 1962 under Medicine.

    7)Define Nucleoside and Nucleotide.
    A).Nucleoside: It consists of a sugar molecule attached to a nitogen base Nucleotide:. It consists of a sugar molecule attached to a nitrogen base and a phosphate group.

    8).Semi-conservative method
    A).Semi-conservative mode of DNA replication was proposed by Watson and Crick in 1953.parent DNA act as a template strand and the daughter strands are newly synthesised.The new daughter DNA contain one parental DNA strand and one newly synthesised strand.

    9)DNA and RNA.
    A). DNA:
    It is a double stranded molecule acting as univeral genetic material.DNA contains deoxy ribose sugar molecule in it's structure.Udergoes autocatalysis and heterocatalysis.Contains Thymine as one of the nitogen base.
    RNA:
    It is a single stranded molecule which act as a genetic material in the absence of DNA molecule.RNA contains ribose sugar in it's structure.Undergoes translation to synthesise protein as a result of transcription by DNA.Contains Uracil instead of Thymine as nitrogen base.

    10)Types of RNA & functions.
    A)There are three types of RNA.They are _m-RNA-It is called messenger-RNA. It is transcribed from the DNA and carries the information for the protein synthesis.
    _t-RNA-It is called transfer-RNA. It has stem loop structure. It carries amino acids to the site of protein synthesis and has anti-codon site which would be complementary to the mRNA sequence.
    _r-RNA- It is called ribosomal-RNA. It is the site for the synthesis of proteins. It will help in attachment of the mRNA with the ribosomes.

    T.Mohan Sai Charan
    DZ - 54

    ReplyDelete
    Replies
    1. DEAR SAI CHARAN,

      GOOD, BUT NEXT TIME PUBLISH IN A PROPER WAY.

      WRITE THE FULL QUESTION

      Delete
  12. U-3. Mendelian Inheritance

    11)Test Cross and Back Cross.
    A).Test Cross:. The cross made between the F1 hybrid with it's recessive parent.It is done to know the homozygosity of the F1 hybrid.
    Back Cross:. The cross made between the F1 hybrid with any one of the parents.It is done in order to achieve offspring with a genetic identity which is closer to that of the parent.

    12) Law of Dominance.
    A)Mendel's law stating that when two alleles of an inherited pair is heterozygous, then, the allele that is expressed is dominant whereas the allele that is not expressed is recessive. The expression of the dominant allele suppressing the recessive allele is termed as Law of Dominance.

    13) Second law of Mendelian Inheritance.
    A)The Law of Independant Assortment of Gametes which states that * When two or more characteristics are inherited, individual hereditary factors assort independently during gamete production, giving different traits an equal opportunity of occurring together.*

    14) Complete Linkage and Incomplete Linkage.
    A)Complete Linkage: It is defined as the state in which two loci are so close together that alleles of these loci are virtually never separated by crossing over. The closer the physical location of two genes on the DNA, the less likely they are to be separated by a crossing-over event.
    Incomplete Linkage:. When the genes were loosly linked on a chromosome and show higher percentage of recombination. In such condition non parental type of gametes are formed.
    Incomplete linkage produces new combinations of the genes in the progeny due to the formation of chiasma or crossing over in between the linked genes present on homologous chromosomes.

    15) Linkage and Crossing Over.
    A).Linkage:. It is the tendency of DNA sequences that are close together on a chromosome to be inherited together during the meiosis phase of sexual reproduction.
    Crossing Over:. It is the process where 2 homologous chromosome sister chromatids pair up with each other and exchange different segments of genetic material to form 2 recombinant chromosome sister chromatids.

    T.Mohan Sai Charan
    DZ - 54

    ReplyDelete
  13. U-4. Plant Breeding

    16)Plant breeding:
    A)Phenomena of development of new varieties of plants possessing desirable characters from the already existing varieties. 
    Objectives:
    Obtain high yield variety. 
    Improve quality, size, shape, colour, taste. 
    Improve disease, drought and pest resistance. 

    17)Emasculation:
    A)Removal of male sex organ without any damage to female reproductive organ. 

    18)Acclimitisation:
    A)The newly introduced varieties has to adopt or adjust itself to the changed climatic conditions. 

    19)Hybridisation:
    A)Crossing of two plants of dissimilar genotype. 
    Objectives:
    To crate genetic variation. 
    Segregation and recombination produce many new gene. 

    20) Types of chromosomal mutations:
    A).deletion:remove of small part 
    .inversion:reattachment of same chromosome
    .translocation:repetation of same gene sequence
    .nondisjunction:transfer of a part of chromosome to another
    .duplication:failure of chromosomes to separate during meiosis. 

    T.Mohan Sai Charan
    DZ - 54

    ReplyDelete
    Replies
    1. DEAR SAI CHARAN,

      GOOD, BUT NEXT TIME PUBLISH IN A PROPER WAY.

      WRITE THE FULL QUESTION

      Delete
  14. U-5. Breeding,Crop Improvement & Biotechnology

    21)Inbreeding lines:
    A)Production of offsprings from the mating of individuals that are closely related genetically. 

    22).Mutagens:
    A)The physical or chemical agent significantly increases the mutation. 
    Physical mutagens:radiation and heat 
    Chemical mutagens:basic analogs, alkylating agents, metals, deaminating agents, intercalating agents 

    23)RFLP:
    A)restriction fragment length polymorphism
    Objectives:
    Allow the transfer of novel genes from related wild species. 
    Establish genetic relationships between sexually incomparable crop plants. 

    24)RAPD:
    A)random amplified polymorphic dna
    Objectives:
    These markers are employed in the construction of genetic map. 
    Used to distinguish between variety based on difference in DNA sequence

    25)DNA markers:
    A)It is a small segment of known DNA that is used in molecular biology to identify sequence of genome in a pool of unknown DNA.

    T.Mohan Sai Charan
    DZ - 54

    ReplyDelete
    Replies
    1. DEAR SAI CHARAN,

      GOOD, BUT NEXT TIME PUBLISH IN A PROPER WAY.

      WRITE THE FULL QUESTION

      Delete
    2. Thanks for your feedback madam.
      Next time I will publish in a proper way.

      Delete
  15. Good evening mam, this is N.Prashanth kumar NB-37 submitting my botany assignment.
    1.define embroyology? name eminent indian embryologists?
    A.the branch of biology and medicine concerned with the study of embryos and their development.
    samo of the eminent indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)

    2.Define Tapetum?
    A. The tapetum is a specialised layer of nutritive cells found within the anther, of flowering plants, where it is located between the sporangenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.

    3.Define Endothecium?
    A. In angiosperms, the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures, thickenings often develop in the cell walls of the endothecium, probably aiding dehiscence.

    4.Define microspore?
    A. Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote.

    5. Define Palaenology?
    A. Palynology is the study of plant pollen, spores and certain microscopic plankton organisms in both living and fossil form.

    6. Define megasporangium? and mention types in it?
    A. the structure in certain spore-bearing plants in which the megaspores are formed.
    Megagametophytes of flowering plants may be described according to the number of megaspores developing, as either monosporic, bisporic, or tetrasporic. these are the types of megasporangium.

    7. define monosporic, bisporoic, tetrasporic types of embryo sac?
    A. Based on the number of megaspores, embryo sacs can be divided into three types: monosporic, bisporic, and tetrasporic.
    1.monosporic type: it is also known as Polygonum-type embryo sac, meiosis of the diploid megaspore mother cell in the nucellus produces four haploid megaspores. Three of the megaspores, usually those at the micropylar end of the nucellus, subsequently undergo programmed cell death, leaving only one functional megaspore.
    2.bisporic type: bisporic embryo sacs, meiosis produces only two megaspores, each containing two haploid nuclei, due to the absence of cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropyle then undergoes programmed cell death, leaving a single functional megaspore with two haploid nuclei.
    3. tetrasporic type: In tetrasporic embryo sacs, cell plates fail to form after both meiotic divisions, resulting in a single four-nucleate megaspore.

    8.define the terms fertilization and syngamy? and name the scientists who coined dthe names?
    A. fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
    syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.

    9. Define double fertilisation and triple fusion?
    A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
    triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.

    10. Define endosperm? mention the types in it.
    A. a nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus. Three main types of endosperm development in flowering plants are: 1.Nuclear type. 2.Cellular type and 3.Helobial type.





    ReplyDelete
    Replies
    1. DEAR PRASANTH,
      GOOD PRESENTATION. NEXT TIME DO BETTER.

      Delete
  16. Good afternoon mam, this is N.Prashanth kumar NB-37. submitting the reamining part of my botany assignment.

    11. Define ruminate endosperm?
    A. the condition in which the endosperm is dissected by in-growths of the seed coat, is a common condition in the palms.

    12. Define Helobial type of endosperm?
    A. It is an intermediate type between the nuclear and cellular types. The first division is accompanied by cytokinesis but the subsequent ones are free nuclear. The chamber towards micropylar end of embryo sac is usually much larger than the chamber towards chalazal end.

    13.Mention the differences between dicot and monocot embryos?
    A. Monocots : 1. contains one cotyledon
    2. usually parallel venation
    3. vascular bundales are usually complexy arranged.
    4. fibrous root system is present
    5. floral parts are usually in multiples of three
    Dicots : 1. contains 2 cotyledons
    2. usually veins are network like
    3. vascular bundles are usually arranged in rings
    4. tap root system is present
    5. floral parts are usually in the multiples of four or five

    14. Define scutellum?
    A. The large, shield-shaped cotyledon of the embryo of a grass plant, specialized for the absorption of food from the endosperm.The scutellum is considered to represent the first leaf or cotyledon.

    15. Define polyembryony?
    A. the production of more than one embryo from one egg is known as polyembryony.

    ReplyDelete
  17. I am K.Vinod babu
    NB-59
    Submitting my botany assignment.

    1.define embroyology? name eminent indian embryologists?
    A.the branch of biology and medicine concerned with the study of embryos and their development.
    samo of the eminent indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)

    2.Define Tapetum?
    A. The tapetum is a specialised layer of nutritive cells found within the anther, of flowering plants, where it is located between the sporangenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.

    3.Define Endothecium?
    A. In angiosperms, the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures, thickenings often develop in the cell walls of the endothecium, probably aiding dehiscence.

    4.Define microspore?
    A. Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote.

    5. Define Palaenology?
    A. Palynology is the study of plant pollen, spores and certain microscopic plankton organisms in both living and fossil form.

    6. Define megasporangium? and mention types in it?
    A. the structure in certain spore-bearing plants in which the megaspores are formed.
    Megagametophytes of flowering plants may be described according to the number of megaspores developing, as either monosporic, bisporic, or tetrasporic. these are the types of megasporangium.

    7. define monosporic, bisporoic, tetrasporic types of embryo sac?
    A. Based on the number of megaspores, embryo sacs can be divided into three types: monosporic, bisporic, and tetrasporic.
    1.monosporic type: it is also known as Polygonum-type embryo sac, meiosis of the diploid megaspore mother cell in the nucellus produces four haploid megaspores. Three of the megaspores, usually those at the micropylar end of the nucellus, subsequently undergo programmed cell death, leaving only one functional megaspore.
    2.bisporic type: bisporic embryo sacs, meiosis produces only two megaspores, each containing two haploid nuclei, due to the absence of cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropyle then undergoes programmed cell death, leaving a single functional megaspore with two haploid nuclei.
    3. tetrasporic type: In tetrasporic embryo sacs, cell plates fail to form after both meiotic divisions, resulting in a single four-nucleate megaspore.

    8.define the terms fertilization and syngamy? and name the scientists who coined dthe names?
    A. fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
    syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.

    9. Define double fertilisation and triple fusion?
    A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
    triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.

    10. Define endosperm? mention the types in it.
    A. a nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus. Three main types of endosperm development in flowering plants are: 1.Nuclear type. 2.Cellular type and 3.Helobial type.

    11. Define ruminate endosperm?
    A. the condition in which the endosperm is dissected by in-growths of the seed coat, is a common condition in the palms.


    ReplyDelete
  18. I am k.vinod babu.
    NB-59
    Submitting my remaining botany assignment.

    12. Define Helobial type of endosperm?
    A. It is an intermediate type between the nuclear and cellular types. The first division is accompanied by cytokinesis but the subsequent ones are free nuclear. The chamber towards micropylar end of embryo sac is usually much larger than the chamber towards chalazal end.

    13.Mention the differences between dicot and monocot embryos?
    A. Monocots : 1. contains one cotyledon
    2. usually parallel venation
    3. vascular bundales are usually complexy arranged.
    4. fibrous root system is present
    5. floral parts are usually in multiples of three
    Dicots : 1. contains 2 cotyledons
    2. usually veins are network like
    3. vascular bundles are usually arranged in rings
    4. tap root system is present
    5. floral parts are usually in the multiples of four or five

    14. Define scutellum?
    A. The large, shield-shaped cotyledon of the embryo of a grass plant, specialized for the absorption of food from the endosperm.The scutellum is considered to represent the first leaf or cotyledon.

    15. Define polyembryony?
    A. the production of more than one embryo from one egg is known as polyembryony.

    ReplyDelete
    Replies
    1. DEAR VINOD
      DEAR PRASANTH,
      GOOD PRESENTATION. NEXT TIME DO BETTER.

      Delete
  19. This is M.Avinash NB-13
    Submitting my botany assignment.

    1)Define Embrology?
    A:It is the branch of Biology that deals with the "study of embryos"but in general terms it include the sex organ development,male and female gametes formation,fertilization,endosperm and embryo formation.

    2)Define Tapetum?
    A:The innermost layer that attain the level of maximum maturity during pollen-tetrad stage.It is composed of a single layer of cells and is characterised by the presence of dense cytoplasm and prominent nuclei.

    3)Define Endothecium.
    A:It is remarkably identified by their radially elongated structure.It is rarely multilayered and it produces "fibrous bands" which helps in time of anther dehiscence.

    4)Define Microspore?
    A:It is formed by microsporogenesis and is responsible for the development of male gametophyte .These are the results of meiosis and usually smaller in size.

    5)Define Palynology?
    A:The shape,size of microspore or pollengrain.Exine miscrosculpturing and number position character of aperture are great taxonomic importance.These are study under seperate branch called "Palynology".

    6)What is Megasporangium and mention its types.
    A:Megasporangium is a structure in angiosperm that produces female gametophytes called megaspores.It is borne in pairs at the base of scales of the cones.It is also called "ovule".
    TYPES:
    a)Orthotropous ovule
    b)Anatropous ovule
    c)Hemianatropous ovule
    d)Campylotropous ovule
    e)Amphitropous ovule
    f)Circinotropous ovule.

    7)Define Monosporic,Bisporic,Tetrasporic embryosacs.
    A:Monosporic embryosac:In this type of embryo development 3 megaspores of tetrad gets degenerate and one remain functional and forms embryosac.
    Bisporic embyrosac:When 2 megasporic nuclei takespart in the formation of embryosac.Both the nuclei are genetically different.
    tetrasporic embryosac:In this type,due to failure of cytokinesis 1 and 2 a four nucleate coenomegaspore tetrad is formed and all 4 nuclei participate in the formation of embryosac.

    8)Define Fertilization.Who coined the term "Fertilization".
    A:It is a process in sexual reproduction that involves the union of male and female gametes to produce a zygote.The term fertilization was coined by"Oscar Hertwig"(1876).

    9)Define a)"Double fetilization" or "Syngamy"and b)"Triple fusion".
    A:a)Double fertilization:It is the process in which 2 male gametes fuse with the female gamete and the secondary nucleus respectively to form the zygote and the endosperm.
    b)Triple fusion:It can be defined as the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant,giving rise to triploid nucleus called "primary endosperm nucleus"(PEN),which later develops into the endosperm.

    10)Define Endosperm and mention its types.
    A:The endosperms are very vital parts of the fertilized embryo.An endosperm forms the surrounding tissue of the growing embryo.The primary endosperm nucleus divides repeatedly.It forms polyploidy nutritive tissue called endosperm.These are of 3 types.
    They are: 1)Nuclear type
    2)Cellular type
    3)Helobial type
    There is a special type of endosperm called as Ruminate endosperm.

    ReplyDelete
  20. This is M.Avinash NB-13
    Submitting remaining of my botany assignment.

    10)Define Endosperm and mention its types.
    A:The endosperms are very vital parts of the fertilized embryo.An endosperm forms the surrounding tissue of the growing embryo.The primary endosperm nucleus divides repeatedly.It forms polyploidy nutritive tissue called endosperm.These are of 3 types.
    They are: 1)Nuclear type
    2)Cellular type
    3)Helobial type
    There is a special type of endosperm called as Ruminate endosperm.

    11)Define Ruminate type of endosperm.
    A:The condition in which the endosperm is dissected by ingrowths of the seed coat,is a common condition in palms.Ruminate endosperm forms when the seed coat intrudes inward via meristematic growth.

    12)Define Helobial endosperm.
    A:This type of endosperm occurs in the order "Helobiales".In this case,first division of primary endosperm nucleus is followed by a transverse wall.This wall divide the embryo sac into a small chalazal chamber and a large micropylar chamber.Then the nuclei in each chamber divide by free nuclear divisions.But,there are few nuclear divisions in the chalazal chamber.The endosperm in this chamber degenerate.Walls develop between nuclei in micropylar chamber.It produces cellular endosperm.

    13)Mention the differences between Dicot and Monocot embryo.
    A:Dicot embryo:An embryo with 2 cotyledons and plumule is distal.Coleoptile,Coleorhiza are absent and Scutellum is also absent.
    Monocot embryo:An embryo with 1 cotyledon and plumule is lateral.Coleoptile,Coleorhiza are present and scutellum is present.

    14)Define Scutellum.
    A:It is the characteristic features of monocot only.The monocot consists of a large and shield shaped cotyledon known as "Scutellum".

    15)Define Polyembyrony.
    A:The formation of more than one embryo from a single fertilized ovum or in a single seed.

    16)Mention the objectives of "Polyembryony".
    A:Objectives of Polyembryony:
    1)To determine whether polyembryony confers a competitive advantage to V.rossicum.
    2)Assess whether this advantage,if present,is more pronounced in intra or interspecific competition, and
    3)To determine whether the competitive advantage ,if present,is proportional to the number of embryos per seed.
    Thank you Madam.

    ReplyDelete
  21. Iam s. Karuna kumari NB:46
    Submitting my botany assignment.
    1)Define embryology?
    A) It is branch of biology deals with the study of embryo but in general terms it include the sex organ development of male and female gamete formation, fertilization, endosperm and embryo formation.
    2)Difference between Dicot and monocot? A) Dicot embryo :An embryo with two cotyledons and plumule is distal coleoptile, coleorhiza, are absent.scutellum is also absent.
    Monocot embryo:An embryo with one cotyledon and plumule lateral coleoptile, coleorhiza are present scutellum is present.
    3)Define scutellum?
    A) It is the characteristics feature of monocot only. The monocot consists of large and shield shaped cotyledon is known as "scutellum "
    4)Define polyembryony?
    A) The formation of more than one embryo from a single fertilized ovum (or) in a single seed.
    5)Mention the objectivies of polyembryony?
    A) objectivies of polyembryony :To determine whether polyembryony confers a competitive advance to v. Rossicum.whether in intra (or) intraspecific compitation and. They are 1.nuclear type 2.cellular type 3)Helobial type.
    6)Define ruminate type of endosperm?
    A)The condition in which the endosperm dissected by in growths of the seed coat is common condition in palms. Ruminate endosperm form when the seed coat inward viameristamatic growth is called "ruminate endosperm ".
    7)Define Helobial endosperm?
    A) This is type of endosperm occurs in the order of "helobials"in this case of first division of primary endosperm nucleus is followed by transverse cell. This wall is devided to embryo sac into small chalazal chamber. Than the nuclei in each chamber devided by a free nucleic divisions. The micropylar chamber produces cellular endosperm.
    8)Define double and triple fusion?
    A) Double fertilization :It is the process in which two male gamets fuse with the female gamete and the secondary nucleus respectively to form the zygote and the endosperm. Triple fusion :It can be defined as the fusion envoluing two polar nuclei and a sperm nucleus that occurs in double fertilization in seed plant, gives rise to triploid nucleus is called "Primary Endosperm Nucleus "(PEN).

    ReplyDelete
    Replies
    1. DEAR s. Karuna kumari NB:46,
      WRITE PROPERLY

      Delete
  22. I am k.mary
    NB-10
    I am submitting botany assignment
    1.define embroyology and name the eminent Indian embryologists ?
    A.the branch of biology and medicine concenerd with the study of embryos and their development.samo of the eminent Indian embryologists are 1.johannes Peter Muller(1801-1858) . Julius kollamann( 1834-1918) 3.Hans spemann(1869-1941)

    2.Define Tapetum?
    A.The Tapetum is a specialised layer of nutritive cells found within the anther,of flowering planrs,where it is located between the sporangenous tissue and the anther wall.Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursor for the pollen coat.

    3.Define Endothecium?
    A.In angiosperms,the layer of cells lying beneath the epidermis of the anther matures, thickenings often develop in the cell walls of the Endothecium probably aiding dehiscnce

    4.Define microspore?
    A.Microspore are land plant spores that develop into male gametopgtes , whereas megaspors devlop into female gametophytes.The male gametophyte gives raise to sperm cells, which are used for fertilization of an egg cell to form a zygoe.

    5.Define palaenology?
    A.Palynology is the study of plant pollen, spores and certain microscopic plankton organisam in both living and fossil form.

    6.Define megasporangium? And mention types in it ?
    A.The structure in certain spore-bearing plants in which the megasporangium are formed.
    Megagametophytes of flowering plants may be described according to the number of megasporic,bisporic ,or tetrasporic.these are the types of megaspirangium.

    7.define minosporic ,bisporic ,tetraspiric types of embryos sac ?
    A.Based on the number of megaspores , embryo sacs can be divided into three types: minosporic ,bisporic ,and tetraspiric.
    1.monospiric types: it is all known as polygonum-type embryo sac,meiosis of the diploid megaspore mother cell in the nucellus produces four haploid megaspores There of the megaspores,usually those at the micropylar end of the nucellus,ssubsequently undergo programmed cell death, leaving only one functional megaspires.
    2.bisporic types: bisporic embryo sacs,meiosis produces only two megaspores, each containing two haploid nuclei, due to the absence of cytokinesis and cell plate formation following the second meiotic division.The megaspores nearest the micropyle then undergoes programmed cell death,leaving a single functional megaspore with two haploud nuclei.
    3. Teteasporic types:in terasotic embryo sacs,cell plates fail to form after both meiotic divisions, resulting in a single four-nucleate megaspire.


    ReplyDelete
    Replies
    1. DEAR k.mary,
      GOOD,
      WRITE YOUR NAME PROPERLY

      Delete
  23. Iam karuna kumari NB:46
    Submitting remaining of my botany assignment
    9)Define endosperm and mention it types?
    A) The endosperm are very vital parts of the fertilized embryo. An endosperm forms the surrounding tissue of the growing embryo. The primary endosperm nucleus devides respectively. It form polyploid nutritive tissue called endosperm these are three types.
    1)nuclear type
    2)helobial type
    3)cellular type.
    10)Define fertilization? Who coined term fertilization?
    A) It is a process in sexual reproduction that involves the union of male and female gamete to produce a zygote. The term fertilization was coined by "Oscar Hertwig"(1876).
    11)Microspore?
    A) The microspore is oval (or) round contains dense cytoplasm, centrally placed nucleus. The microspore is surrounded by a stratified wall called sporoderm. The sporoderm is made up of two layers.
    1)outer exine
    2)inner exine.
    12)Endothecium?
    A) The cells of the endothecium are radially elongated and shows fibrous bands. The fibrous bands are made up of callose an arise from the inner tangential walls. Usually fibrous bands are "u"shaped.fibrous bands are absent in Htdrocharitaceae, saprophytes and cleistogamous flowers. It is single layered in coccinia double layered.
    13)Tapetum?
    A) Tapetum is the innermost layer of anther walls, and it completely surrounds the sporogenous tissue. The cells contain dense cytoplasm with prominent nuclei. Tapetum transports the nutrients to the developing sporocytes. Tapetal cells are pigmented and it is red brown in apple or violet in anemone.
    14)Define monosporic, bisporic, tetrasporic embryosac?
    A) Monosporic type of embryo sac :In the type of two divisions are followed by wall formation. It results in the formation of linear tetrads of megaspore of the four megaspore three will be degenerated and only one is functional.
    Bisporic type of embryo sac :The first meotic division of megaspore mother cell is formed by wall formation. So that two cell are formed, they are called dyad cells.
    Tetrasporic type of embryo sac :In this type, the embryo sac develops from all the four megaspore nuclei.During megasporogenisis the megaspore mother cell undergoes meiosis with out wall formation. There are seven types of embryo sacs.
    15)What is megasporangium? Mention their types?

    A) Megasporangium is a structure in angiosperm that produces female gametophyte called "megaspore"It is a borne in a base of scales and cones. is also called as "ovule ".
    TYPES:
    A) orthotropous ovule :It is an erect ovule. It is also called atropous ovule. In this type of micropyle, chalaza, funicle in polygoniaceae.
    B) Anatropous ovule :It is an inverted ovule. In this type of the body of the completely inverted due to unilateral growth of funicle.
    C) Hemitropous ovule:In this type of body of the ovule is completely inverted due to unilateral growth of funicle. This type of ovule is called malphigiaceae.
    D) campylotropous ovule:In this type of the body of the ovule is placed at right angles to the funicle. This type of ovule is called cappardiaceae.
    E) Amphitropous ovule:This is also called transverse ovule. In this type of the body of the ovule shows more curvature. This type of ovule called as alismaceae.
    F) circinotropous ovule :In this type of funiculus is long and completely encircles the ovule eg:plumbaginaceae.

    ReplyDelete
    Replies
    1. DEAR karuna kumari NB:46
      GOOD,
      WRITE YOUR NAME PROPERLY.

      Delete
  24. Name.Ch.Bhargavi
    Section.NB-32
    I am submitting my botany assignment.
    1.define embryology? Name eminent indian embryologist?
    A.the branch of biology and medicine concerned with the study of embryos and their development.
    Same of the eminent indian embryologists are 1.johnnes Peter Muller(1081-1858) 2.julius kollamann(1834-1918) 3.hanns spemann(1869-1941).

    2.define tapetum?
    A. The tapetum is specialised layer of nutritive cells found within the anther, of flowering plants where it is located between the sporogenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.

    3.define endothecium?
    A. In angiosperms the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures thickinings often develops in the cell walls of the endothecium probably aiding dehiscene.

    4.Define microspore?
    A. Microspores are land plant spores that develop into male gametophytes whereas megaspores develop into female gametophytes.The male gametophyte gives rise to sperm cells which are used for fertilisation of an egg cell to form a zygote.

    5.Define palynology?
    A. Palynology is the study of plant pollen, spores and certain microscopic plankton organisms in both living and fossil form.

    6.Define megasporangium?
    A. The structure in certain spore-bearing plants in which the megaspores are formed.
    Megagametophytes of flowering plants may be described according to the number of megaspores developing as either monosporic, bisporic, and tetrasporic. These are the types of megasporangium.

    7.Define monosporic,bisporic, tetrasporic types of embryos?
    A. Based on the number of megaspores embyosacs are divided into three types monosporic, bishopric and tetrasporic.
    1.monosporic type:it is also known as polygonum-type embyosac, meiosis of the diploid megaspore mother cell in the nucellus produce four haploid megaspores.Three of the megaspores usually those are at the micropylar end of the nucellus, subsequently undergo programmed cell death, leaving only one functional megaspore.
    2.bisporic type:bisporic embyosacs,meiosis produces only two megaspores each containing two haploid nuclei due to the absence of cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropylar then the undergoes cell death, leaving the single functional megaspore with two haploid nuclei.
    3.tetrasporic type: In the tetrasporic embryosacs the cell plates fail to form after both meiotic divisions resulting a single fournucleate megaspore.


    ReplyDelete
  25. I am K. Mary
    NB-10

    8.define the terms fertilization and synga y? And name the scientists who coined dthe names ?
    A.fertilisation:Fertilisation is fusion of gametes to form a new organism of the same species. Whilhelm August Oscar Hertwig(1849-1922) discovered Fertilisation
    Syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse Kondrshov coined the name.it considered as the modified form of the Fertilisation.

    9.Define double Fertilisation and triple fusion ?
    A.double Fertilisation : fertilization characteristics of seed plants in which one sprem nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
    Triple fusion:the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the fomation of the endosperm.

    10.Define endosperm ? Mention the types in it.
    A.a ntritive tissue in seed plans formed within the embryo sac by division of the endosperm nucleus.Three main types of endosperm development in flowering plants are:1.Nuclear type.2.cellular type and 3.Helopial type.

    11.Define ruminate endosperm ?
    A. The condition in which the endosperm is dissected by in growths of the seed coat,is a common condition in the plans.

    12.Dfine Helobial type of endosperm?
    A.It is an intermediate type between the nuclear and cellular types.The first division is accompanied by cytokinesis no esis but to the subseqent ones are free nuclear. The chamber towards micropylar end of embryo sac is usually much larger than the chamber towards chalazal end.

    13.Mention the differences between dicot and monocot embryos ?
    A. Monocots : 1. Contains one cotyledon
    2. Usually parallel venation
    3. Vascular bundales are usually complexy arranged.
    4.fibrous roots system is present
    5.floral Parts are usually in multiples of three
    Dicots : 1.contains 2.cotyledons
    2.usually veins are network like
    3.vascular bundles are usually arranged n rings
    4.tap root system is present
    5.floral parts are usually in the multiples of four or five

    14.Define scutellum?
    A. The large, shield-shaped cotyledon of the embryo of a grass plant,specialized for the absorption of food from the endsperm.The scutellum is considered to represent the frist leaf or cotyledon.

    15.Define polyembryony?
    A. The production of more than one embryo from one egg is known as polyembryony.

    ReplyDelete
  26. Name.Ch.Bhargavi
    Section.NB-32
    I am submitting my botany assignment.
    1.define embryology? Name eminent indian embryologist?
    A.the branch of biology and medicine concerned with the study of embryos and their development.
    Same of the eminent indian embryologists are 1.johnnes Peter Muller(1081-1858) 2.julius kollamann(1834-1918) 3.hanns spemann(1869-1941).

    2.define tapetum?
    A. The tapetum is specialised layer of nutritive cells found within the anther, of flowering plants where it is located between the sporogenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.

    3.define endothecium?
    A. In angiosperms the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures thickinings often develops in the cell walls of the endothecium probably aiding dehiscene.

    4.Define microspore?
    A. Microspores are land plant spores that develop into male gametophytes whereas megaspores develop into female gametophytes.The male gametophyte gives rise to sperm cells which are used for fertilisation of an egg cell to form a zygote.

    5.Define palynology?
    A. Palynology is the study of plant pollen, spores and certain microscopic plankton organisms in both living and fossil form.

    6.Define megasporangium?
    A. The structure in certain spore-bearing plants in which the megaspores are formed.
    Megagametophytes of flowering plants may be described according to the number of megaspores developing as either monosporic, bisporic, and tetrasporic. These are the types of megasporangium.

    7.Define monosporic,bisporic, tetrasporic types of embryos?
    A. Based on the number of megaspores embyosacs are divided into three types monosporic, bishopric and tetrasporic.
    1.monosporic type:it is also known as polygonum-type embyosac, meiosis of the diploid megaspore mother cell in the nucellus produce four haploid megaspores.Three of the megaspores usually those are at the micropylar end of the nucellus, subsequently undergo programmed cell death, leaving only one functional megaspore.
    2.bisporic type:bisporic embyosacs,meiosis produces only two megaspores each containing two haploid nuclei due to the absence of cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropylar then the undergoes cell death, leaving the single functional megaspore with two haploid nuclei.
    3.tetrasporic type: In the tetrasporic embryosacs the cell plates fail to form after both meiotic divisions resulting a single fournucleate megaspore.


    ReplyDelete
  27. I am CH.Bhargavi
    NB-32
    8.define the terms fertilization and syngamy? and name the scientists who coined dthe names?
    A. fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
    syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.

    9. Define double fertilisation and triple fusion?
    A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
    triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.

    10. Define endosperm? mention the types in it.
    A. a nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus. Three main types of endosperm development in flowering plants are: 1.Nuclear type. 2.Cellular type and 3.Helobial type.

    11. Define ruminate endosperm?
    A. the condition in which the endosperm is dissected by in-growths of the seed coat, is a common condition in the palms.

    ReplyDelete
  28. I am CH.Bhargavi
    NB-32
    12. Define Helobial type of endosperm?
    A. It is an intermediate type between the nuclear and cellular types. The first division is accompanied by cytokinesis but the subsequent ones are free nuclear. The chamber towards micropylar end of embryo sac is usually much larger than the chamber towards chalazal end.

    13.Mention the differences between dicot and monocot embryos?
    A. Monocots : 1. contains one cotyledon
    2. usually parallel venation
    3. vascular bundales are usually complexy arranged.
    4. fibrous root system is present
    5. floral parts are usually in multiples of three
    Dicots : 1. contains 2 cotyledons
    2. usually veins are network like
    3. vascular bundles are usually arranged in rings
    4. tap root system is present
    5. floral parts are usually in the multiples of four or five

    14. Define scutellum?
    A. The large, shield-shaped cotyledon of the embryo of a grass plant, specialized for the absorption of food from the endosperm.The scutellum is considered to represent the first leaf or cotyledon.

    15. Define polyembryony?
    A. the production of more than one embryo from one egg is known as polyembryony.


    ReplyDelete
  29. Good evening mam,
    I am N.Nikhila
    NB-22
    Submitting my botany assignment.

    1.Define embroyology? Name eminent Indian embryologists?
    A.The branch of biology and medicine concerned with the study of embryos and their development.
    some of the eminent Indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)

    2.Define Tapetum?
    A. The tapetum is a specialised layer of nutritive cells found within the anther, of flowering plants, where it is located between the sporangenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.

    3.Define Endothecium?
    A. In angiosperms, the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures, thickenings often develop in the cell walls of the endothecium, probably aiding dehiscence.

    4.Define microspore?
    A. Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote.

    5. Define Palynology?
    A. Palynology is the study of plant pollen, spores and certain microscopic plankton organisms in both living and fossil form.

    6. Define megasporangium? and mention types in it?
    A. the structure in certain spore-bearing plants in which the megaspores are formed.
    Megagametophytes of flowering plants may be described according to the number of megaspores developing, as either monosporic, bisporic, or tetrasporic. these are the types of megasporangium.

    7. Define monosporic, bisporoic, and tetrasporic types of embryo sac?
    A. Based on the number of megaspores, embryo sacs can be divided into three types: monosporic, bisporic, and tetrasporic.
    1.Monosporic type: it is also known as Polygonum-type embryo sac, meiosis of the diploid megaspore mother cell in the nucellus produces four haploid megaspores. Three of the megaspores, usually those at the micropylar end of the nucellus, subsequently undergo programmed cell death, leaving only one functional megaspore.
    2.Bisporic type: Bisporic embryo sacs, meiosis produces only two megaspores, each containing two haploid nuclei, due to the absence of cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropyle then undergoes programmed cell death, leaving a single functional megaspore with two haploid nuclei.
    3. Tetrasporic type: In tetrasporic embryo sacs, cell plates fail to form after both meiotic divisions, resulting in a single four-nucleate megaspore.

    8.Define the terms fertilization and syngamy? and name the scientists who coined the terms?
    A. Fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
    Syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.

    9. Define double fertilisation and triple fusion?
    A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
    triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.

    10. Define endosperm? mention the types in it.
    A. A nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus. Three main types of endosperm development in flowering plants are: 1.Nuclear type. 2.Cellular type and 3.Helobial type.

    ReplyDelete
  30. Good evening mam,
    I am N.Nikhila
    NB-22
    Submitting my botany assignment.

    1.Define embroyology? Name eminent Indian embryologists?
    A.The branch of biology and medicine concerned with the study of embryos and their development.
    some of the eminent Indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)

    2.Define Tapetum?
    A. The tapetum is a specialised layer of nutritive cells found within the anther, of flowering plants, where it is located between the sporangenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.

    3.Define Endothecium?
    A. In angiosperms, the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures, thickenings often develop in the cell walls of the endothecium, probably aiding dehiscence.

    4.Define microspore?
    A. Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote.

    5. Define Palynology?
    A. Palynology is the study of plant pollen, spores and certain microscopic plankton organisms in both living and fossil form.

    6. Define megasporangium? and mention types in it?
    A. the structure in certain spore-bearing plants in which the megaspores are formed.
    Megagametophytes of flowering plants may be described according to the number of megaspores developing, as either monosporic, bisporic, or tetrasporic. these are the types of megasporangium.

    7. Define monosporic, bisporoic, and tetrasporic types of embryo sac?
    A. Based on the number of megaspores, embryo sacs can be divided into three types: monosporic, bisporic, and tetrasporic.
    1.Monosporic type: it is also known as Polygonum-type embryo sac, meiosis of the diploid megaspore mother cell in the nucellus produces four haploid megaspores. Three of the megaspores, usually those at the micropylar end of the nucellus, subsequently undergo programmed cell death, leaving only one functional megaspore.
    2.Bisporic type: Bisporic embryo sacs, meiosis produces only two megaspores, each containing two haploid nuclei, due to the absence of cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropyle then undergoes programmed cell death, leaving a single functional megaspore with two haploid nuclei.
    3. Tetrasporic type: In tetrasporic embryo sacs, cell plates fail to form after both meiotic divisions, resulting in a single four-nucleate megaspore.

    8.Define the terms fertilization and syngamy? and name the scientists who coined the terms?
    A. Fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
    Syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.

    9. Define double fertilisation and triple fusion?
    A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
    triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.

    10. Define endosperm? mention the types in it.
    A. A nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus. Three main types of endosperm development in flowering plants are: 1.Nuclear type. 2.Cellular type and 3.Helobial type.

    ReplyDelete
  31. I am N.Nikhila ,
    NB-22,
    Submitting my remaining assignment mam,

    11. Define ruminate endosperm?
    A. The condition in which the endosperm is dissected by in-growths of the seed coat, is a common condition in the palms.

    12.Define Helobial type of endosperm?
    A. It is an intermediate type between the nuclear and cellular types. The first division is accompanied by cytokinesis but the subsequent ones are free nuclear. The chamber towards micropylar end of embryo sac is usually much larger than the chamber towards chalazal end.

    13.Mention the differences between dicot and monocot embryos?
    A. Monocots : 1. contains one cotyledon
    2. usually parallel venation
    3. vascular bundales are usually complexy arranged.
    4. fibrous root system is present
    5. floral parts are usually in multiples of three
    Dicots : 1. contains 2 cotyledons
    2. usually veins are network like
    3. vascular bundles are usually arranged in rings
    4. tap root system is present
    5. floral parts are usually in the multiples of four or five

    14. Define scutellum?
    A. The large, shield-shaped cotyledon of the embryo of a grass plant, specialized for the absorption of food from the endosperm.The scutellum is considered to represent the first leaf or cotyledon.

    15. Define polyembryony?
    A. The production of more than one embryo from one egg is known as polyembryony.

    Thank you madam.

    ReplyDelete
  32. Good morning mam
    I am CH.Kalanjali
    NB-28
    1.define embroyology? name eminent indian embryologists?
    A.the branch of biology and medicine concerned with the study of embryos and their development.
    samo of the eminent indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)

    2.Define Tapetum?
    A. The tapetum is a specialised layer of nutritive cells found within the anther, of flowering plants, where it is located between the sporangenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.

    3.Define Endothecium?
    A. In angiosperms, the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures, thickenings often develop in the cell walls of the endothecium, probably aiding dehiscence.

    4.Define microspore?
    A. Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote.

    5. Define Palynology?
    A. Palynology is the study of plant pollen, spores and certain microscopic plankton organisms in both living and fossil form.

    6. Define megasporangium? and mention types in it?
    A. the structure in certain spore-bearing plants in which the megaspores are formed.
    Megagametophytes of flowering plants may be described according to the number of megaspores developing, as either monosporic, bisporic, or tetrasporic. these are the types of megasporangium.

    7. define monosporic, bisporoic, tetrasporic types of embryo sac?
    A. Based on the number of megaspores, embryo sacs can be divided into three types: monosporic, bisporic, and tetrasporic.
    1.monosporic type: it is also known as Polygonum-type embryo sac, meiosis of the diploid megaspore mother cell in the nucellus produces four haploid megaspores. Three of the megaspores, usually those at the micropylar end of the nucellus, subsequently undergo programmed cell death, leaving only one functional megaspore.
    2.bisporic type: bisporic embryo sacs, meiosis produces only two megaspores, each containing two haploid nuclei, due to the absence of cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropyle then undergoes programmed cell death, leaving a single functional megaspore with two haploid nuclei.
    3. tetrasporic type: In tetrasporic embryo sacs, cell plates fail to form after both meiotic divisions, resulting in a single four-nucleate megaspore.

    8.define the terms fertilization and syngamy? and name the scientists who coined dthe names?
    A. fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
    syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.

    9. Define double fertilisation and triple fusion?
    A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
    triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.

    ReplyDelete
  33. I am CH.Kalanjali
    NB-28
    10. Define endosperm? mention the types in it.
    A. a nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus. Three main types of endosperm development in flowering plants are: 1.Nuclear type. 2.Cellular type and 3.Helobial type.

    11. Define ruminate endosperm?
    A. the condition in which the endosperm is dissected by in-growths of the seed coat, is a common condition in the palms.

    12. Define Helobial type of endosperm?
    A. It is an intermediate type between the nuclear and cellular types. The first division is accompanied by cytokinesis but the subsequent ones are free nuclear. The chamber towards micropylar end of embryo sac is usually much larger than the chamber towards chalazal end.

    13.Mention the differences between dicot and monocot embryos?
    A. Monocots : 1. contains one cotyledon
    2. usually parallel venation
    3. vascular bundales are usually complexy arranged.
    4. fibrous root system is present
    5. floral parts are usually in multiples of three
    Dicots : 1. contains 2 cotyledons
    2. usually veins are network like
    3. vascular bundles are usually arranged in rings
    4. tap root system is present
    5. floral parts are usually in the multiples of four or five

    14. Define scutellum?
    A. The large, shield-shaped cotyledon of the embryo of a grass plant, specialized for the absorption of food from the endosperm.The scutellum is considered to represent the first leaf or cotyledon.

    15. Define polyembryony?
    A. the production of more than one embryo from one egg is known as polyembryony.
    Thank you mam

    ReplyDelete
    Replies
    1. DEAR CH.Kalanjali,

      GOOD PRESENTATION. NEXT TIME DO BETTER.

      Delete
  34. This is G. Udaya sri NB-30
    Submitting my botany assignment.

    1)Define Embrology? A:It is the branch of Biology that deals with the "study of embryos"but in general terms it include the sex organ development,male and female gametes formation,fertilization,endosperm and embryo formation. 2)Define Tapetum? A:The innermost layer that attain the level of maximum maturity during pollen-tetrad stage.It is composed of a single layer of cells and is characterised by the presence of dense cytoplasm and prominent nuclei. 3)Define Endothecium. A:It is remarkably identified by their radially elongated structure.It is rarely multilayered and it produces "fibrous bands" which helps in time of anther dehiscence. 4)Define Microspore? A:It is formed by microsporogenesis and is responsible for the development of male gametophyte .These are the results of meiosis and usually smaller in size. 5)Define Palynology? A:The shape,size of microspore or pollengrain.Exine miscrosculpturing and number position character of aperture are great taxonomic importance.These are study under seperate branch called "Palynology". 6)What is Megasporangium and mention its types. A:Megasporangium is a structure in angiosperm that produces female gametophytes called megaspores.It is borne in pairs at the base of scales of the cones.It is also called "ovule". TYPES: a)Orthotropous ovule b)Anatropous ovule c)Hemianatropous ovule d)Campylotropous ovule e)Amphitropous ovule f)Circinotropous ovule. 7)Define Monosporic,Bisporic,Tetrasporic embryosacs. A:Monosporic embryosac:In this type of embryo development 3 megaspores of tetrad gets degenerate and one remain functional and forms embryosac. Bisporic embyrosac:When 2 megasporic nuclei takespart in the formation of embryosac.Both the nuclei are genetically different. tetrasporic embryosac:In this type,due to failure of cytokinesis 1 and 2 a four nucleate coenomegaspore tetrad is formed and all 4 nuclei participate in the formation of embryosac. 8)Define Fertilization.Who coined the term "Fertilization". A:It is a process in sexual reproduction that involves the union of male and female gametes to produce a zygote.The term fertilization was coined by"Oscar Hertwig"(1876).

    9)Define a)"Double fetilization" or "Syngamy"and b)"Triple fusion". A:a)Double fertilization:It is the process in which 2 male gametes fuse with the female gamete and the secondary nucleus respectively to form the zygote and the endosperm. b)Triple fusion:It can be defined as the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant,giving rise to triploid nucleus called "primary endosperm nucleus"(PEN),which later develops into the endosperm.

    ReplyDelete
  35. This G. Udaya sri NB-30 submitting the remaining part of my assignment

    10)Define Endosperm and mention its types. A:The endosperms are very vital parts of the fertilized embryo.An endosperm forms the surrounding tissue of the growing embryo.The primary endosperm nucleus divides repeatedly.It forms polyploidy nutritive tissue called endosperm.These are of 3 types. They are: 1)Nuclear type 2)Cellular type 3)Helobial type There is a special type of endosperm called as Ruminate endosperm. 11)Define Ruminate type of endosperm. A:The condition in which the endosperm is dissected by ingrowths of the seed coat,is a common condition in palms.Ruminate endosperm forms when the seed coat intrudes inward via meristematic growth. 12)Define Helobial endosperm. A:This type of endosperm occurs in the order "Helobiales".In this case,first division of primary endosperm nucleus is followed by a transverse wall.This wall divide the embryo sac into a small chalazal chamber and a large micropylar chamber.Then the nuclei in each chamber divide by free nuclear divisions.But,there are few nuclear divisions in the chalazal chamber.The endosperm in this chamber degenerate.Walls develop between nuclei in micropylar chamber.It produces cellular endosperm. 13)Mention the differences between Dicot and Monocot embryo. A:Dicot embryo:An embryo with 2 cotyledons and plumule is distal.Coleoptile,Coleorhiza are absent and Scutellum is also absent. Monocot embryo:An embryo with 1 cotyledon and plumule is lateral.Coleoptile,Coleorhiza are present and scutellum is present. 14)Define Scutellum. A:It is the characteristic features of monocot only.The monocot consists of a large and shield shaped cotyledon known as "Scutellum". 15)Define Polyembyrony. A:The formation of more than one embryo from a single fertilized ovum or in a single seed. 16)Mention the objectives of "Polyembryony".  A:Objectives of Polyembryony: 1)To determine whether polyembryony confers a competitive advantage to V.rossicum. 2)Assess whether this advantage,if present,is more pronounced in intra or interspecific competition, and 3)To determine whether the competitive advantage ,if present,is proportional to the number of embryos per seed. Thank you Madam.

    ReplyDelete
    Replies
    1. DEAR G. Udaya sri NB-30,
      WRITE PROPERLY.

      Delete
    2. This G. Udaya sri NB-30 submitting the edited remaining part of my assignment

      10)Define Endosperm and mention its types.
      A:The endosperms are very vital parts of the fertilized embryo.An endosperm forms the surrounding tissue of the growing embryo.The primary endosperm nucleus divides repeatedly.It forms polyploidy nutritive tissue called endosperm.These are of 3 types. They are: 1)Nuclear type 2)Cellular type 3)Helobial type There is a special type of endosperm called as Ruminate endosperm.

      11)Define Ruminate type of endosperm.
      A:The condition in which the endosperm is dissected by ingrowths of the seed coat,is a common condition in palms.Ruminate endosperm forms when the seed coat intrudes inward via meristematic growth.

      12)Define Helobial endosperm.
      A:This type of endosperm occurs in the order "Helobiales".In this case,first division of primary endosperm nucleus is followed by a transverse wall.This wall divide the embryo sac into a small chalazal chamber and a large micropylar chamber.Then the nuclei in each chamber divide by free nuclear divisions.But,there are few nuclear divisions in the chalazal chamber.The endosperm in this chamber degenerate.Walls develop between nuclei in micropylar chamber.It produces cellular endosperm.


      13)Mention the differences between Dicot and Monocot embryo.
      A:Dicot embryo:An embryo with 2 cotyledons and plumule is distal.Coleoptile,Coleorhiza are absent and Scutellum is also absent. Monocot embryo:An embryo with 1 cotyledon and plumule is lateral.Coleoptile,Coleorhiza are present and scutellum is present.


      14)Define Scutellum.
      A:It is the characteristic features of monocot only.The monocot consists of a large and shield shaped cotyledon known as "Scutellum".


      15)Define Polyembyrony.
      A:The formation of more than one embryo from a single fertilized ovum or in a single seed.


      16)Mention the objectives of "Polyembryony".
      A:Objectives of Polyembryony: 1)To determine whether polyembryony confers a competitive advantage to V.rossicum. 2)Assess whether this advantage,if present,is more pronounced in intra or interspecific competition, and 3)To determine whether the competitive advantage ,if present,is proportional to the number of embryos per seed.

      Thank you Madam

      Delete
  36. Good evening madam. I am N.Dakshyini
    NB-18 this is my botany assignment.

    1)Define Embrology? A:It is the branch of Biology that deals with the "study of embryos"but in general terms it include the sex organ development,male and female gametes formation,fertilization,endosperm and embryo formation. 2)Define Tapetum? A:The innermost layer that attain the level of maximum maturity during pollen-tetrad stage.It is composed of a single layer of cells and is characterised by the presence of dense cytoplasm and prominent nuclei. 3)Define Endothecium. A:It is remarkably identified by their radially elongated structure.It is rarely multilayered and it produces "fibrous bands" which helps in time of anther dehiscence. 4)Define Microspore? A:It is formed by microsporogenesis and is responsible for the development of male gametophyte .These are the results of meiosis and usually smaller in size. 5)Define Palynology? A:The shape,size of microspore or pollengrain.Exine miscrosculpturing and number position character of aperture are great taxonomic importance.These are study under seperate branch called "Palynology". 6)What is Megasporangium and mention its types. A:Megasporangium is a structure in angiosperm that produces female gametophytes called megaspores.It is borne in pairs at the base of scales of the cones.It is also called "ovule". TYPES: a)Orthotropous ovule b)Anatropous ovule c)Hemianatropous ovule d)Campylotropous ovule e)Amphitropous ovule f)Circinotropous ovule. 7)Define Monosporic,Bisporic,Tetrasporic embryosacs. A:Monosporic embryosac:In this type of embryo development 3 megaspores of tetrad gets degenerate and one remain functional and forms embryosac. Bisporic embyrosac:When 2 megasporic nuclei takespart in the formation of embryosac.Both the nuclei are genetically different. tetrasporic embryosac:In this type,due to failure of cytokinesis 1 and 2 a four nucleate coenomegaspore tetrad is formed and all 4 nuclei participate in the formation of embryosac. 8)Define Fertilization.Who coined the term "Fertilization". A:It is a process in sexual reproduction that involves the union of male and female gametes to produce a zygote.The term fertilization was coined by"Oscar Hertwig"(1876).

    9)Define a)"Double fetilization" or "Syngamy"and b)"Triple fusion". A:a)Double fertilization:It is the process in which 2 male gametes fuse with the female gamete and the secondary nucleus respectively to form the zygote and the endosperm. b)Triple fusion:It can be defined as the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant,giving rise to triploid nucleus called "primary endosperm nucleus"(PEN),which later develops into the endosperm.

    ReplyDelete
    Replies
    1. Good evening madam. I am N.Dakshyini
      NB-18 this is my botany assignment.
      1)Define Embrology?
      A:It is the branch of Biology that deals with the "study of embryos"but in general terms it include the sex organ development,male and female gametes formation,fertilization,endosperm and embryo formation.

      2)Define Tapetum?
      A:The innermost layer that attain the level of maximum maturity during pollen-tetrad stage.It is composed of a single layer of cells and is characterised by the presence of dense cytoplasm and prominent nuclei.

      3)Define Endothecium.
      A:It is remarkably identified by their radially elongated structure.It is rarely multilayered and it produces "fibrous bands" which helps in time of anther dehiscence.

      4)Define Microspore?
      A:It is formed by microsporogenesis and is responsible for the development of male gametophyte .These are the results of meiosis and usually smaller in size.

      A:The shape,size of microspore or pollengrain.Exine miscrosculpturing and number position character of aperture are great taxonomic importance.These are study under seperate branch called "Palynology".

      6)What is Megasporangium and mention its types.
      A:Megasporangium is a structure in angiosperm that produces female gametophytes called megaspores.It is borne in pairs at the base of scales of the cones.It is also called "ovule". TYPES: a)Orthotropous ovule
      b)Anatropous ovule
      c)Hemianatropous ovule
      d)Campylotropous ovule
      e)Amphitropous ovule
      f)Circinotropous ovule.

      7)Define Monosporic,Bisporic,Tetrasporic embryosacs.
      A:Monosporic embryosac:In this type of embryo development 3 megaspores of tetrad gets degenerate and one remain functional and forms embryosac. Bisporic embyrosac:When 2 megasporic nuclei takespart in the formation of embryosac.Both the nuclei are genetically different. tetrasporic embryosac:In this type,due to failure of cytokinesis 1 and 2 a four nucleate coenomegaspore tetrad is formed and all 4 nuclei participate in the formation of embryosac.
      8)Define Fertilization.Who coined the term "Fertilization".
      A:It is a process in sexual reproduction that involves the union of male and female gametes to produce a zygote.The term fertilization was coined by"Oscar Hertwig"(1876).

      9)Define a)"Double fetilization" or "Syngamy"and b)"Triple fusion".
      A:a)Double fertilization:It is the process in which 2 male gametes fuse with the female gamete and the secondary nucleus respectively to form the zygote and the endosperm. b)Triple fusion:It can be defined as the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant,giving rise to triploid nucleus called "primary endosperm nucleus"(PEN),which later develops into the endosperm.

      Delete
  37. Good evening madam. This is N. Dakshayini NB-18. this is the remaining part of my assignment.

    10)Define Endosperm and mention its types. A:The endosperms are very vital parts of the fertilized embryo.An endosperm forms the surrounding tissue of the growing embryo.The primary endosperm nucleus divides repeatedly.It forms polyploidy nutritive tissue called endosperm.These are of 3 types. They are: 1)Nuclear type 2)Cellular type 3)Helobial type There is a special type of endosperm called as Ruminate endosperm. 11)Define Ruminate type of endosperm. A:The condition in which the endosperm is dissected by ingrowths of the seed coat,is a common condition in palms.Ruminate endosperm forms when the seed coat intrudes inward via meristematic growth. 12)Define Helobial endosperm. A:This type of endosperm occurs in the order "Helobiales".In this case,first division of primary endosperm nucleus is followed by a transverse wall.This wall divide the embryo sac into a small chalazal chamber and a large micropylar chamber.Then the nuclei in each chamber divide by free nuclear divisions.But,there are few nuclear divisions in the chalazal chamber.The endosperm in this chamber degenerate.Walls develop between nuclei in micropylar chamber.It produces cellular endosperm. 13)Mention the differences between Dicot and Monocot embryo. A:Dicot embryo:An embryo with 2 cotyledons and plumule is distal.Coleoptile,Coleorhiza are absent and Scutellum is also absent. Monocot embryo:An embryo with 1 cotyledon and plumule is lateral.Coleoptile,Coleorhiza are present and scutellum is present. 14)Define Scutellum. A:It is the characteristic features of monocot only.The monocot consists of a large and shield shaped cotyledon known as "Scutellum". 15)Define Polyembyrony. A:The formation of more than one embryo from a single fertilized ovum or in a single seed. 16)Mention the objectives of "Polyembryony".  A:Objectives of Polyembryony: 1)To determine whether polyembryony confers a competitive advantage to V.rossicum. 2)Assess whether this advantage,if present,is more pronounced in intra or interspecific competition, and 3)To determine whether the competitive advantage ,if present,is proportional to the number of embryos per seed. Thank you Madam.

    ReplyDelete
    Replies
    1. DEAR N. Dakshayini NB-18,

      WRITE PROPERLY

      Delete
    2. Good evening madam. This is N. Dakshayini NB-18. this is the remaining part of my assignment.

      10)Define Endosperm and mention its types.
      A:The endosperms are very vital parts of the fertilized embryo.An endosperm forms the surrounding tissue of the growing embryo.The primary endosperm nucleus divides repeatedly.It forms polyploidy nutritive tissue called endosperm.These are of 3 types. They are: 1)Nuclear type 2)Cellular type 3)Helobial type There is a special type of endosperm called as Ruminate endosperm.

      11)Define Ruminate type of endosperm.
      A:The condition in which the endosperm is dissected by ingrowths of the seed coat,is a common condition in palms.Ruminate endosperm forms when the seed coat intrudes inward via meristematic growth.

      12)Define Helobial endosperm.
      A:This type of endosperm occurs in the order "Helobiales".In this case,first division of primary endosperm nucleus is followed by a transverse wall.This wall divide the embryo sac into a small chalazal chamber and a large micropylar chamber.Then the nuclei in each chamber divide by free nuclear divisions.But,there are few nuclear divisions in the chalazal chamber.The endosperm in this chamber degenerate.Walls develop between nuclei in micropylar chamber.It produces cellular endosperm.

      13)Mention the differences between Dicot and Monocot embryo.
      A:Dicot embryo:An embryo with 2 cotyledons and plumule is distal.Coleoptile,Coleorhiza are absent and Scutellum is also absent. Monocot embryo:An embryo with 1 cotyledon and plumule is lateral.Coleoptile,Coleorhiza are present and scutellum is present.

      14)Define Scutellum.
      A:It is the characteristic features of monocot only.The monocot consists of a large and shield shaped cotyledon known as "Scutellum".

      15)Define Polyembyrony.
      A:The formation of more than one embryo from a single fertilized ovum or in a single seed.

      16)Mention the objectives of "Polyembryony".
      A:Objectives of Polyembryony: 1)To determine whether polyembryony confers a competitive advantage to V.rossicum. 2)Assess whether this advantage,if present,is more pronounced in intra or interspecific competition, and 3)To determine whether the competitive advantage ,if present,is proportional to the number of embryos per seed.

      Thank you Madam.

      Delete
  38. Good evening mam Iam supriya nb -40 submitting my botany assignment .
    1. Define embyology? name eminent indian embryologists?

    Ans: The branch of biology and medicine concerned with the study of embryos and their development .

    Same of the eminent Indian embryologists are:

    1.Johannes Peter muller(1801-1858)

    2.Julius kollmann (1834-1918)

    3. Hans sperma (1869-1941)

    2.Define tapetum?

    Ans: The tapetum is a specialised layer of nutritive cells within the anther , of flowering plants. where it is located between the sporangeous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains,as well as a source of precursors for the pollen coat.

    3.Define endothecium?

    Ans: In angiosperms the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures. thickenings often develop in the cell walls of the endothecium. Probably aiding dehiscene.

    4. Define microspore?

    Ans: microspore are land plant spores that develop into male gamtetophytes, whereas megaspores develop into female gametophytes.The male gametophyte give rise to sperm cells, which are used for fertilization of an egg cell to form a zygote.

    5. Define palynology?

    Ans: palynology is the study of plant pollen, spores and y microscopic plankton organisms in both living and fossil form.

    6. Define megasporangium? and mention the types in it ?

    Ans: the structure in certain spore bearing pants in which the megaspores are formed.
    Megagametophytes of flowering plants may be described according to the number of megaspores developing , as either monosporic , bisporic, tetrasporic.

    These are the three types.

    7. Define monosporic, bisporic, tetrasporic types of embryosac?

    Ans: based on the number of megaspores . embryosacs can be divided into three types :

    1. Monosporic type : it is also known as the polygonum type embryosac. Meiosis of the diploid megaspore mother cell in the nucellus produces four haploid megaspores. three of the megaspores , usually those at the micropylar end of the nucellus subsequently undergo programmed cell death, leaving only one functional megaspore.

    2. Bisporic type : bispore embryosacs, meisos produces only two megaspores, each containing two haploid nuclei due to the absence of t cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropyle then undergo programmed cell death, leaving single functional megaspore with two haploid nuclei.

    3. Tetrasporic type: tetrasporic embryosacs, cell plate fail to form after both meiotic divisions, results in single four nucleate. megaspore.

    ReplyDelete
  39. Good afternoon madam i am ch.pravallika nb -41 submitting my assaingment

    1define embroyology? name eminent indian embryologists?
    A.the branch of biology and medicine concerned with the study of embryos and their development.
    samo of the eminent indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)

    2.Define Tapetum?
    A. The tapetum is a specialised layer of nutritive cells found within the anther, of flowering plants, where it is located between the sporangenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.

    3.Define Endothecium?
    A. In angiosperms, the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures, thickenings often develop in the cell walls of the endothecium, probably aiding dehiscence.

    4.Define microspore?
    A. Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote.

    5. Define Palynology?
    A. Palynology is the study of plant pollen, spores and certain microscopic plankton organisms in both living and fossil form.

    6. Define megasporangium? and mention types in it?
    A. the structure in certain spore-bearing plants in which the megaspores are formed.
    Megagametophytes of flowering plants may be described according to the number of megaspores developing, as either monosporic, bisporic, or tetrasporic. these are the types of megasporangium.

    7. define monosporic, bisporoic, tetrasporic types of embryo sac?
    A. Based on the number of megaspores, embryo sacs can be divided into three types: monosporic, bisporic, and tetrasporic.
    1.monosporic type: it is also known as Polygonum-type embryo sac, meiosis of the diploid megaspore mother cell in the nucellus produces four haploid megaspores. Three of the megaspores, usually those at the micropylar end of the nucellus, subsequently undergo programmed cell death, leaving only one functional megaspore.
    2.bisporic type: bisporic embryo sacs, meiosis produces only two megaspores, each containing two haploid nuclei, due to the absence of cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropyle then undergoes programmed cell death, leaving a single functional megaspore with two haploid nuclei.
    3. tetrasporic type: In tetrasporic embryo sacs, cell plates fail to form after both meiotic divisions, resulting in a single four-nucleate megaspore.

    8.define the terms fertilization and syngamy? and name the scientists who coined dthe names?
    A. fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
    syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.

    9. Define double fertilisation and triple fusion?
    A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
    triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.

    ReplyDelete
    Replies
    1. DEAR karthik venkatsai,
      WRITE YOUR NAME PROPERLY,
      WRITE ALL THE QUESTIONS PROPERLY,
      LATE SUBMISSION

      Delete
  40. I am pravallaki nb -41 submitting my assaingment

    11. Define ruminate endosperm?
    A. The condition in which the endosperm is dissected by in-growths of the seed coat, is a common condition in the palms.

    12.Define Helobial type of endosperm?
    A. It is an intermediate type between the nuclear and cellular types. The first division is accompanied by cytokinesis but the subsequent ones are free nuclear. The chamber towards micropylar end of embryo sac is usually much larger than the chamber towards chalazal end.

    13.Mention the differences between dicot and monocot embryos?
    A. Monocots : 1. contains one cotyledon
    2. usually parallel venation
    3. vascular bundales are usually complexy arranged.
    4. fibrous root system is present
    5. floral parts are usually in multiples of three
    Dicots : 1. contains 2 cotyledons
    2. usually veins are network like
    3. vascular bundles are usually arranged in rings
    4. tap root system is present
    5. floral parts are usually in the multiples of four or five

    14. Define scutellum?
    A. The large, shield-shaped cotyledon of the embryo of a grass plant, specialized for the absorption of food from the endosperm.The scutellum is considered to represent the first leaf or cotyledon.

    15. Define polyembryony?
    A. The production of more than one embryo from one egg is known as polyembryony.

    ReplyDelete
    Replies
    1. DEAR pravallaki nb -41,
      ANSWER ALL THE QUESTIONS PROPERLY
      WRITE YOUR NAME PROPERLY

      Delete
  41. Good evening mam,I am CH.Chandanamrutha,NB-52
    Submitting my botany assignment. 1.Define embroyology? Name eminent Indian embryologists?
    A.The branch of biology and medicine concerned with the study of embryos and their development.
    some of the eminent Indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)

    2.Define Tapetum?
    A. The tapetum is a specialised layer of nutritive cells found within the anther, of flowering plants, where it is located between the sporangenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.

    3.Define Endothecium?
    A. In angiosperms, the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures, thickenings often develop in the cell walls of the endothecium, probably aiding dehiscence.

    4.Define microspore?
    A. Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote.

    5. Define Palynology?
    A. Palynology is the study of plant pollen, spores and certain microscopic plankton organisms in both living and fossil form.

    6. Define megasporangium? and mention types in it?
    A. the structure in certain spore-bearing plants in which the megaspores are formed.
    Megagametophytes of flowering plants may be described according to the number of megaspores developing, as either monosporic, bisporic, or tetrasporic. these are the types of megasporangium.

    7. Define monosporic, bisporoic, and tetrasporic types of embryo sac?
    A. Based on the number of megaspores, embryo sacs can be divided into three types: monosporic, bisporic, and tetrasporic.
    1.Monosporic type: it is also known as Polygonum-type embryo sac, meiosis of the diploid megaspore mother cell in the nucellus produces four haploid megaspores. Three of the megaspores, usually those at the micropylar end of the nucellus, subsequently undergo programmed cell death, leaving only one functional megaspore.
    2.Bisporic type: Bisporic embryo sacs, meiosis produces only two megaspores, each containing two haploid nuclei, due to the absence of cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropyle then undergoes programmed cell death, leaving a single functional megaspore with two haploid nuclei.
    3. Tetrasporic type: In tetrasporic embryo sacs, cell plates fail to form after both meiotic divisions, resulting in a single four-nucleate megaspore.

    8.Define the terms fertilization and syngamy? and name the scientists who coined the terms?
    A. Fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
    Syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.

    9. Define double fertilisation and triple fusion?
    A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
    triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.

    10. Define endosperm? mention the types in it.
    A. A nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus. Three main types of endosperm development in flowering plants are: 1.Nuclear type. 2.Cellular type and 3.Helobial type.

    ReplyDelete
  42. Mam,I am CH.Chandanamrutha
    NB-52,
    Submitting my remaining assignment.

    11.Define ruminate endosperm?
    A. The condition in which the endosperm is dissected by in-growths of the seed coat, is a common condition in the palms.

    12.Define Helobial type of endosperm?
    A. It is an intermediate type between the nuclear and cellular types. The first division is accompanied by cytokinesis but the subsequent ones are free nuclear. The chamber towards micropylar end of embryo sac is usually much larger than the chamber towards chalazal end.

    13.Mention the differences between dicot and monocot embryos?
    A. Monocots : 1. contains one cotyledon
    2. usually parallel venation
    3. vascular bundales are usually complexy arranged.
    4. fibrous root system is present
    5. floral parts are usually in multiples of three
    Dicots : 1. contains 2 cotyledons
    2. usually veins are network like
    3. vascular bundles are usually arranged in rings
    4. tap root system is present
    5. floral parts are usually in the multiples of four or five

    14. Define scutellum?
    A. The large, shield-shaped cotyledon of the embryo of a grass plant, specialized for the absorption of food from the endosperm.The scutellum is considered to represent the first leaf or cotyledon.

    15. Define polyembryony?
    A. The production of more than one embryo from one egg is known as polyembryony.

    ReplyDelete
  43. Good evening mam,I am N.Prashanthi,
    NB-11,Submitting my botany assignment.

    1.Define embroyology? Name eminent Indian embryologists?
    A.The branch of biology and medicine concerned with the study of embryos and their development.
    some of the eminent Indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)

    2.Define Tapetum?
    A. The tapetum is a specialised layer of nutritive cells found within the anther, of flowering plants, where it is located between the sporangenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.

    3.Define Endothecium?
    A. In angiosperms, the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures, thickenings often develop in the cell walls of the endothecium, probably aiding dehiscence.

    4.Define microspore?
    A. Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote.

    5. Define Palynology?
    A. Palynology is the study of plant pollen, spores and certain microscopic plankton organisms in both living and fossil form.

    6. Define megasporangium? and mention types in it?
    A. the structure in certain spore-bearing plants in which the megaspores are formed.
    Megagametophytes of flowering plants may be described according to the number of megaspores developing, as either monosporic, bisporic, or tetrasporic. these are the types of megasporangium.

    7. Define monosporic, bisporoic, and tetrasporic types of embryo sac?
    A. Based on the number of megaspores, embryo sacs can be divided into three types: monosporic, bisporic, and tetrasporic.
    1.Monosporic type: it is also known as Polygonum-type embryo sac, meiosis of the diploid megaspore mother cell in the nucellus produces four haploid megaspores. Three of the megaspores, usually those at the micropylar end of the nucellus, subsequently undergo programmed cell death, leaving only one functional megaspore.
    2.Bisporic type: Bisporic embryo sacs, meiosis produces only two megaspores, each containing two haploid nuclei, due to the absence of cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropyle then undergoes programmed cell death, leaving a single functional megaspore with two haploid nuclei.
    3. Tetrasporic type: In tetrasporic embryo sacs, cell plates fail to form after both meiotic divisions, resulting in a single four-nucleate megaspore.

    8.Define the terms fertilization and syngamy? and name the scientists who coined the terms?
    A. Fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
    Syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.

    ReplyDelete
    Replies
    1. DEAR N.Prashanthi, NB-11
      GOOD, BUT LATE SUBMISSION

      Delete
  44. Mam,I am N.Prashanthi,NB-11,
    submitting my remaining assaignment.

    9. Define double fertilisation and triple fusion?
    A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
    triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.

    10. Define endosperm? mention the types in it.
    A. A nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus. Three main types of endosperm development in flowering plants are: 1.Nuclear type. 2.Cellular type and 3.Helobial type.

    11.Define ruminate endosperm?
    A. The condition in which the endosperm is dissected by in-growths of the seed coat, is a common condition in the palms.

    12.Define Helobial type of endosperm?
    A. It is an intermediate type between the nuclear and cellular types. The first division is accompanied by cytokinesis but the subsequent ones are free nuclear. The chamber towards micropylar end of embryo sac is usually much larger than the chamber towards chalazal end.

    13.Mention the differences between dicot and monocot embryos?
    A. Monocots : 1. contains one cotyledon
    2. usually parallel venation
    3. vascular bundales are usually complexy arranged.
    4. fibrous root system is present
    5. floral parts are usually in multiples of three
    Dicots : 1. contains 2 cotyledons
    2. usually veins are network like
    3. vascular bundles are usually arranged in rings
    4. tap root system is present
    5. floral parts are usually in the multiples of four or five

    14. Define scutellum?
    A. The large, shield-shaped cotyledon of the embryo of a grass plant, specialized for the absorption of food from the endosperm.The scutellum is considered to represent the first leaf or cotyledon.

    15. Define polyembryony?
    A. The production of more than one embryo from one egg is known as polyembryony.

    ReplyDelete
    Replies
    1. DEAR N.Prashanthi,NB-11,
      GOOD BUT LATE SUBMISSION

      Delete