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REPRODUCTION

REPRODUCTION

 Reproduction is a process by which every living organism produce an organism like their own. 
I.   Types of reproduction :
(a)    Asexual reproduction : In this type of reproduction only one parent organism either mother or father produces new organism.
(b)    Sexual reproduction : In this type of reproduction both parent are involved & produces new organisms.
 

II.    Asexual reproduction in unicellular organism :
1.    Binary fission : During this process, two daughter organisms of equal sizes are formed from one parent by the division of the parent body. This is the most common method of reproduction in algae, fungi and bacteria (fig.).

      Multiple fission: Sonetimes the nucleus divides into many daughter nuclei. The daughter nuclei arrange at the periphery of the parent cell, and a bit of    cytoplasm around each daughter nuclei is present. Nucleus develops an outer                        membrane.   Finally, the multinulceated body divides into many daughter cells. e.g. Blue green algae.

    
(2)    Budding : In this type of reproduction, a small outgrowth appears on the body of the organism. This outgrowth is called a bud. The buds grow and finally detach from the parent body and begin to live as independent organisms. 

(3)    Fragmentation : This takes place in algae like spirogyra and oscillatoria. The filament of the alga breaks into two or more pieces called fragments, and the process is known as fragmentation. Each fragment the grows into a new plant.


(4)    Spore formation : Some lower plants such as ferns, mosses, lichens and fungi reproduce through spore formation under unfavourable conditions. Spores are tiny, microscopic bodies, which are covered by hard protective coats. The protective coats enable them to tide over adverse environmental conditions. When favourable conditions return, each spore gives rise to a new individual. 

ASEXUAL REPRODUCTION IN PLANTS

    When reproduction takes place only from the vegetative parts of plant known as vegetative reproduction.

    (a)    Natural vegetative propagation.
    (b)     Artificial vegetative propagation.

I   Natural vegetative propagation :
    1.   Natural propagation by leaf : Vegetative propagation by leaves can be seen in very few plants like bryophyllum and begonia. In these plants buds are produced on leaf margins. These buds after falling on the ground grow into new                      plants.
    2.   Natural propagation by stem : Underground stems are modified for storage of food. ?These underground stems produce several new plants from their buds. Modified stems like tuber, bulb, rhizome and corm help the plants to multiply.
    3.   Natural propagation by root : Roots also help in vegetative propagation. For example, sweet potato and dahlia give rise to new plants from their fleshy roots. (figure)

II.   Artificial vegetative propagation :
    1.  Grafting : In this commonly practiced method a new variety is obtained from the mother plant (figure). In this process a detached part of one plant is inserted into the stem or the root system of another plant.
     
         The short piece of detached shoot containing several buds is called scion. The lower portion of the plant that is fixed to the soil by its roots system is called the stock. They establish vascular connection with each other after a few days. 

    2.   Layering : In this method a young branch is bent towards the ground and covered with moist soil. After some days,

...
roots develop from the covered part, which is in contact with the soil. This is called a layer and the process is called            layering. The branch is then separated from the parent plant and allowed to grow into a new independent plant.

    

   3.  Cutting : In this method a healthy young branch of a plant having leaf buds is cut out and planted in moist soil (figure). The branch develops root and grows into a new plant. Bougainvillea, sugarcane, rose and grapes are grown from                  cuttings.

SEXUAL REPRODUCTION IN PLANTS

    Flower is a reproductive part of plant. Which contain male & female sex organ & produce ovum & pollen grain. 
    A normal flower consists of four whorls namely sepals, petals, androecium and gynoecium (figure).
    The androecium is the male reproductive part of the flower. Androecium may consist of one or more tube-like stamens. Each stamen consists of thin stalk called filament and a two-lobed head called the anther. Anther contains pollen grains          which produce male gametes.
    The pistil or gynoecium is the female reproductive part of the flower. Each pistil consist of stigma, style, and ovary. The ovary contains one or more ovules. 


POLLINATION

    Pollination is the process by which pollen grains from the anther of a flower are transferred to the stigma of the same flower or another flower.
I.   Types of pollination : 
    There are two types of pollination which are described below : 
1.    Self-Pollination or Autogammy :
    It is the process of transfer of pollen from anther to the stigma of the same flower or to the stigma of another flower of the same plant.


2.   Cross-pollination or Allogamy :
    It is the process of transfer of pollen from the anther of a flower to the stigma of a flower of another plant of the same species or sometimes of very closely related species.
   

FERTILISATION

    After successful pollination the stigma secretes nutrients for the lodged pollen grains. The pollen grains absorb these nutrients and grow to form a thin tube called pollen tube. This grows into the stigma in down the style (figure). It grows until it reaches the ovule and enters inside it. The pollen tube contains two male gametes. After reaching the ovule, it releases the male gametes, one of which fused with the egg to form the zygote. This process of fusion of a male gamete with a female gamete is called fertilization. The zygote develops into an embryo. 


 

FRUIT & SEED FORMATION

    After fertilization the ovary grows into a fruit and the ovules inside it become seeds. The other parts of the flower such as sepals, petals, and stamens fall off. A fruit is actually a biologically ripened ovary.

EXERCISE - I

Q.1    Name four forms of stems which can propagate vegetatively.

Q.2    Name two organisms which reproduce by budding.

Q.3    Name a plant which reproduce by spores.

Q.4    What is the mode of reproduction in spirogyra?

Q.5    What is the name of male and female parts of a flower ?

Q.6    Name one plant whose fruits have a fibrous coat which makes them float in water.

Q.7    What is a zygote and how is it formed ?

Q.8    Write two characteristics of insect pollinated flowers.

Q.9    What is tissue culture ?

Q.10    Name the male and female reproductive parts of a flower.

Q.11    What is the function of pollens in flowering plants ?

Q.12    What is the main difference between asexual and sexual reproduction ?

Q.13    Make a labelled diagram of the flower showing reproductive parts in it.

Q.14    How is fertilization brought about in a flower ?

Q.15    What do you understand by fertilization ? Explain it with a neat and well-labelled diagram.

 

EXERCISE - II

Q.1    A method in which roots are initiated on the stem while still attached with the parent plant is called -
        (A) grafting             (B) budding 
       (C) layering             (D) tissue culture 

Q.2    Hydra reproduces by -
        (A) budding            (B) spore formation
        (C) binary fission   (D) fragmentation

Q.3    Pollen grains are produced in -
       (A) anther               (B) filament
       (C) stigma              (D) style 

Q.4    Seeds in a matured ovary develop from -
        (A) ovule               (B) stigma
        (C) ovum              (D) pollen grains

Q.5    Seeds and fruits dispersed by wind have -
    (A) wings    
    (B) hairs
    (C) censer mechanism     
     (D) all of these 

Q.6    Ferns, mosses, lichen and fungi reproduce through -
         (A) spore formation          (B) binary fission
         (C) budding                      (D) fragmentation 

Q.7    A plant can be grown from tissue-culture is -
         (A) orchid                        (B) pear
         (C) grapevine                   (D) cherry 

Q.8    Stigma, style and ovary are the parts of -
        (A) androecium               (B) gynoecium
        (C) anther                        (D) sepals 

Q.9    Which does not belong to bisexual flower ?
        (A) mustard                   (B) rose
        (C) petunia                    (D) papaya 

ANSWER KEY

1.     C    2.    A    3.     A    4.      A
5.     B    6.     A    7.     A    8.    B
9.    D    

 

EXERCISE - III

1.    Androphore structure is formed by :
    (A) Internode    (B) Node
    (C) Sepals    (D) Petals

2.    When embryo develops from a haploid cell of embryosac, other than egg cell the process is known as
    (A) Apogamy    (B) Apospory    
    (C) Adventive embryony     (D) Diplo spory

3.    Which of the following statement is correct
    (A) Flower is a modified root    
    (B) Flower is a modified shoot
    (C) Flower is a modified leaf    
    (D) Flower is a modified inflorescence

4.    Androgenic haploid plants are produced from
    (A) Pollen grains    
    (B) Connective tissues
    (C) Tapetum
    (D) Wall of the anther

5.    Apomixis was discovered by
    (A) Leeuwenhoek    (B) Winkler
    (C) Juel & murbeck    (D) Navaschin & guignard

6.    In which Era angiosperms originated :-
    (A) Coenozoic    (B) Jurassic    
    (C) Mesozoic    (D) Holozoic

7.    Which of the following is monocarpic plant :-
    (A) Shisham    (B) Mango
    (C) Pinus    (D) Bamboo

8.    Anthophore is :-
    (A) Receptacle between two carpels 
    (B) Inter node between Androecium and Gynoecium
    (C) Internode between calyx and corolla
    (D) None of these

9.    Which is the most logical sequence with reference to the life cycle of angiosperm-
    (A) Germination, endosperm formation, seed dispersal, double fertilization.
    (B) Cleavage, fertilization, grafting, fruit formation
    (C) Pollination fertilization, seed formation & germination
    (D) Maturation, mitosis, differentiation

10.    After culturing the anther of a plants few diploid plant were got along with haploid plant. Which of the following part might have given rise to diploid plant -
    (A) Vegetative cell of pollen    
    (B) Exine of pollen wall
    (C) Cells of anther wall
    (D) Generative cell of pollen

11.    Capsella is angiosperm because it possess 
    (A) Seed    (B) Pollen grain
    (C) Vascular tissue    (D) Fruit

12.    Anther of Arceuthobium plant is :-
    (A) Tetra sporangiate    (B) Bisporangiate
    (C) Monosporangiate        (D) (A) and (B) both

13.    Which part of the reproductive structure produces both enzyme & hormones
    (A) Archesporium    (B) middle layer
    (C) Tapetum    (D) Endo thecium
14.    Ubisch bodies are produced in
    (A) embryosac    (B) Endothecium    
    (C) Pollen grain    (D) Tapetum

15.    The mature male gametophyte in angiosperm is represented by
    (A) Pollen grain
    (B) Germinating pollen grain
    (C) Embryo sac
    (D) Anther

16.    Which structure of pollen grain protect it from ultra violet rays
    (A) Sporopollenin    (B) Pollen kitt
    (C) Ubisch body    (D) 1 & 2 both

17.    Tapetum is :-
    (A) Parietal in origin usually the inner most layer of anther wall.
    (B) Modified endothecium of anther wall
    (C) Outer most layer of sporogenous tissue modification
    (D) Parietal in origin and is the inner most layer of ovule wall

18.    Division taking place in sporogenous cell is
    (A) Meiosis    (B) Amitosis    
    (C) Endomitosis    (D) Only mitosis

19.    In Capsella pollen grains are shed at
    (A) One celled stage    (B) Three cell stage
    (C) Three nuclei stage    (D) Two celled stage

20.    Example of polyploid tissue present in an angiosperm plant is
    (A) Perisperm    (B) Embryo
    (C) Tapetum    (D) Placenta

21.    A microspore is a first cell of
    (A) Female gametophyte
    (B) Male gametophyte
    (C) Sporophyte
    (D) Anther

22.    Pollen grains of some plants cause
    (A) Pneumonia    (B) Typhoid
    (C) Allergy    (D) None of these

23.    Anther is generally composed of
    (A) One sporangium    (B) Two sporangium
    (C) Three sporangium    (D) Four sporangium

24.    Anther of Capsella is equivalent to which structure of a fern plant
    (A) Sporangia    (B) Sorus
    (C) Antheridia    (D) Male gametangia

25.    Occurence of more than four spores from Spore mother cells is called 
    (A) Polysiphony    (B) Polyspermy
    (C) Polyspory    (D) Poly embryony

26.    How many cells or nuclei are present in male gametophyte of Capsella
    (A) One    (B) Two
    (C) Three    (D) Many

27.    How many and what type of male gametes are produced by the male gametophyte of Capsella
    (A) One,. multi cilliated    (B) two, biciliated
    (C) two, multi ciliated    (D) two, non motile

28.    The particular type of fossils of pollen grains present in area may be helpful in the exploration of
    (A) Coal    (B) Petrolium
    (C) Fossil pteridophyte    (D) All the above

29.    Ubisch bodies are associated with the development of
    (A) Embryo    (B) Pollen grains
    (C) Endosperm    (D) Embryo sac

30.    In a pollen grain the small nucleus is
    (A) Generative nucleus    (B) Tube nucleus
    (C) Vegetative nucleus    (D) Pollen nucleus

31.    Most reduced size gametophyte is of
    (A) Bryophytes    (B) Pteridophyte
    (C) Gymnosperm    (D) Angiosperm

32.    Pollen grain of Capsella
    (A) Monocolpate    (B) Bicolpate
    (C) Tricolpate    (D) Polycolpate

33.    Essential whorls of a flowers
    (A) Calyx and Corolla
    (B) Corolla and Gynoecium
    (C) Androecium and Gynoecium
    (D) All the above

34.    Filiform pollen grains are found in:-
    (A) Calotropis    (B) Myosotis
    (C) Cyperus    (D) Zostera

35.    Which statement is false:-
    (A) Unisexuality of flower induces cross pollination
    (B) Androgenic plants are developed by Guha & Maheshwari
    (C) Morphological barriers are absent in Gloriosa flower
    (D) All

36.    Isobilateral tetrad is common in :-
    (A) Monocots    (B) Dicots
    (C) Halophia    (D) None of above

37.    Which type of tetrad is found in Magnolia plant :-
    (A) Isobilateral    (B) T-shaped
    (C) Linear    (D) Decussate

38.    Sporopollenin is found in :-
    (A) Exine    (B) Intine
    (C) Cytoplasm    (D) Nucleus

39.    Microsporophyll of Angiosperms is known as:-
    (A) Androecium    (B) Anther
    (C) Filament    (D) Stamen

40.    Main function of endothecium (in anther) is
    (A) Mechanical    (B) Nutritive
    (C) Dehiscence    (D) None of above

41.    Which of the following is wrong statement :-
    (A) Monothecous anthers are found in Malvaceae family
    (B) Middle layer is ephemeral
    (C) Amoeboid tapetum releases ubisch bodies
    (D) Banana is a monocarpic plant

42.    Development of male gametophyte is :-
    (A) Invivo    (B) Insitu
    (C) Both
    (D) None of the above

43.    Pollen grains preserved for long time because of
    (A) Cellulose    (B) Carotenoids
    (C) Ubisch bodies    (D) Sporopollenin

44.    Endothecium, middle layer and tapetum in anther are derived from :-
    (A) Primary sporogenous layer    
    (B) Primary parietal layer
    (C) Both
    (D) None of the above

45.    Which one is female gametophyte
    (A) Embryo    (B) Embryosac
    (C) Endosperm    (D) Pistil

46.    What type of ovule is found in Capsella-
    (A) Orthotropus    (B) Campylotropus
    (C) Anatropus    (D) Hemitropus

47.    The embryo sac of Capsella derives it's nutrition from-
    (A) Sporogenous    (B) Tapetum
    (C) Epithecium    (D) Nucellus

48.    A polygonum type of embryosac is
    (A) 7-celled and 8 nucleate    
    (B) 8-celled and 7-nucleate
    (C) 7-celled and 7-nucleate    
    (D) 8-celled and 8-nucleate

49.    What type of ovule found in Mirabilis
    (A) Anatropous    (B) Orthotropous
    (C) Circinotropous    (D) None

50.    The functional megaspore in Capsella is always
    (A) Micropylar    (B) Chalazal
    (C) All    (D) Any

51.    Crassinucellate ovule shows
    (A) Absence of nucellus
    (B) Well developed nucellus
    (C) Partially developed nucellus
    (D) Modified nucellus

52.    Ovule of an angiosperm is technically equivalent to
    (A) A megasporangium
    (B) A megagametangium
    (C) A micro spore
    (D) A mega spore

53.    Proliferation of integumentary cells at the micropylar region of the ovule in castor develops
    (A) Aril    (B) Funicle
    (C) Caruncle    (D) Apophysis

54.    Caruncle is formed by
    (A) Peduncle    (B) Cotyledons
    (C) Integument    (D) Perisperm

55.    Obturators which help in fertilization are out growth of
    (A) Pollen tube
    (B) Stigma
    (C) Placenta or funiculus
    (D) Pollen grains

56.    Just before fertilization the diploid structure in the ovule of Capsella is
    (A) Pollen tube
    (B) Nucellus/ Sec.nucleus
    (C) Synergids
    (D) Antipodals

57.    Filiform apparatus are found in
    (A) Antipodal cell    (B) Egg cell    
    (C) Secondary nucleus    (D) Synergids

58.    Which type of gametes are present in Capsella 
    (A) Flagellated    (B) Motile
    (C) Non-motile    (D) None of these

59.    Perisperm is
    (A) Persistant nucellus in seed
    (B) Ovule wall
    (C) Ovule coat
    (D) Fossil of haustoria

60.    Free nuclear division in an angiosperm takes place during
    (A) Gamete formation
    (B) Endosperm formation
    (C) Embryo formation
    (D) Flower formation

61.    Archesporial cells in Capsella do not form
    (A) Epidermis
    (B) Endothecium
    (C) Tapetum
    (D) Micro spore mother cell

62.    Raphe and hilum in seed represent
    (A) Nucellus    (B) Funiculus
    (C) Integument    (D) Micropyle

63.    Micropyle in seed helps in the entry of
    (A) Male gamete    (B) Pollen tube
    (C) Water & air    (D) All

64.    Anther of the Moringa plant is:-
    (A) Tetrasporangiate    (B) Monosporangiate
    (C) Bisporangiate    (D) Above (A) & (B) both

65.    The plant in which G.B. Amici discovered pollen tube is:-
    (A) Capsella    (B) Parthenium
    (C) Portulaca    (D) None of above

66.    Megasporophyll is called:-
    (A) Gynoecium    (B) Carpel
    (C) Ovary    (D) Stigma

67.    How many pollen sacs are present in a mature anther 
    (A) 4    (B) 1
    (C) 3    (D) 2

68.    The ovule in which single layer nucellar tissue is present is known as :-
    (A) Crassinucellate    (B) Tenuinucellate
    (C) Amphinucellate    (D) Circinotropous

69.    The structure which is formed on micropyle by elongation of inner integument known as :-
    (A) Sarcotesta    (B) Operculum
    (C) Caruncle    (D) Aril

70.    In which family, endothelium is formed by integuments :-
    (A) Malvaceae    (B) Compositae
    (C) Podostemaceae    (D) Crucifereae

71.    When outer integument becomes fleshy then known as :-
    (A) Aril    (B) Sarcotesta
    (C) Operculum    (D) Caruncle

72.    By which structure, funiculum is attached with ovule 
    (A) Funiculum    (B) Raphe
    (C) Hilum    (D) Placenta

73.    Resupinate type of ovule are :-
    (A) Straight    (B) Inverted
    (C) Transverse    (D) Coiled

74.    The barrier which is present towards the micropyle is known as :-
    (A) Epistase    (B) Hypostase
    (C) Both of the above    (D) None of above

75.    Horizontally oriented ovule in Angiosperm is called 
    (A) Amphitropous    (B) Hemitropous
    (C) Campylotropous    (D) Circinotropous

76.    The structure is formed by integument which helps in germination is called :-
    (A) Aril    (B) Sarcotesta
    (C) Caruncle    (D) Operculum

77.    In anatropous ovule, the micropyle is present:-
    (A) In straight line with funiculum    
    (B) At right angles with funiculum
    (C) At 45° with funiculum
    (D) Side by side with funiculum

78.    In ovule a barrier is present towards the chalaza out side the embryo sac is called:-
    (A) Nucellar beak    (B) Epistase
    (C) Hypostase    (D) Perisperm

79.    Which structure of the ovule will change in the end:-
    (A) Embryosac    (B) Integuments
    (C) Funiculum    (D) All of the above

80.    The special features of the endothecium of anther of Capsella :–
    (A) Radially elongated
    (B) Thickening of cellulose
    (C) Hygroscopic
    (D) All of the above

81.    The type of cells under going meiosis in the flowers are
    (A) Micro spore mother cell & mega spore mother cell
    (B) Ovule & stamen
    (C) Tapetal cells
    (D) Placental cell

82.    Which of the following types of embryosac is mostly found in Angiosperm
    (A) Bisporic polygonum type
    (B) Tetra sporic type
    (C) Monosporic - onagrad type
    (D) Monosporic - polygonum type

83.    In many plants, the sexual reproduction replaced by asexual reproduction it is called
    (A) Semigamy    (B) Apospory
    (C) Apomixis    (D) Amphimixis

84.    "Endostome" and "Exostome" are part of
    (A) Nucellus    (B) Chalaza
    (C) Pollen wall    (D) Micropyle

85.    Pseudo embryo sac is derived from
    (A) Nucellus    (B) Integument
    (C) Placenta    (D) Funiculus

86.    Endothelium is derived from
    (A) Integument    (B) Placenta
    (C) Nucellus    (D) Funiculus

87.    Which type embryosac is found in Plumbago plant
    (A) Monosporic    (B) Bisporic
    (C) Tetra sporic    (D) None of above

88.    Age of the angiosperms known as :-
    (A) Mesozoic Era    (B) Holozoic Era
    (C) Coenozoic Era    (D) Archaeozoic Era

89.    Female gametophyte like pollens are found in :-
    (A) Sorgham    (B) Hyacinthus
    (C) Vinca    (D) None of these

90.    Which type of growth is found in pollen tube :-
    (A) Lateral growth    (B) Apical growth
    (C) Middle growth    (D) No growth

91.    Monosporic eight nucleated embryosac reffered as :-
    (A) Peperomia type    (B) Allium type
    (C) Polygonum type    (D) Oenothera type

92.    When funiculum, chalaza, and micropyle lie in one straight line then ovule is called:
    (A) Amphitropous    (B) Orthotropous
    (C) Campylotropous    (D) Anatropous

93.    Chasmogamy refers to the condition where
    (A) Flowers remains closed
    (B) Flowers absent
    (C) Flowers open
    (D) Flowers gamopetalous

94.    When pollen grains of a flower are transferred to stigma of another flower on a different plant, the process is called
    (A) Geitonogamy    (B) Xenogamy
    (C) Autogamy    (D) Homogamy

95.    When anther and stigma mature at the same time is called as
    (A) Dichogamy    (B) Allogamy
    (C) Xenogamy    (D) Homogamy

96.    Self-pollination means
    (A) Transfer of pollen from anthers to stigma in the same flowers
    (B) Transfer of pollen from one flowers to another on the different plant
    (C) Occurence of male and female sex organ in the same flowers
    (D) Germination of pollen

97.    "Lever mechanism" or "turn pipe mechanism" for pollination is characteristic feature of 
    (A) Antirrhinum    (B) Ocimum
    (C) Salvia    (D) Ficus

98.    Maize is best example of :
    (A) Anemophilous    (B) Ornithophilous
    (C) Entomophilous    (D) Hydrophilous

99.    Translator apparatus is found in
    (A) Mustard    (B) Pea
    (C) Calotropis    (D) Mango

100.    Which type of pollination occurs in Capsella
    (A) Entamophily    (B) Anemophily
    (C) Hydrophily
    (D) None of the above

ANSWER KEYS

1.    A    2.     A    3.     B    4.     A    5.     B    6.     C    7.     D    8.     C    9.     C    10.    C    11.     D    12.     C    13.     C    

14.     D    15.     B    16.     D    17.     A    18.     D    19.     D    20.     C    21.     B    22.     C    23.     D    24.     B    25.     C  

 26.     C    27.     D    28.     D   29.     B    30.     A    31.     D    32.     C    33.     C    34.     D    35.     C    36.     A    37.     D    

38.    A    39.    D    40.    C    41.    C    42.    C    43.    D    44.    B    45.    B    46.    B    47.    D    48.    A    49.    D    50.    B    

51.    B    52.    A    53.    C    54.    C    55.    C    56.    B  57.    D    58.    C    59.    A    60.    B    61.    A    62.    B    63.    C    

64.    C    65.    C    66.    B    67.    D    68.    B    69.    B    70.    B    71.    B    72.    C    73.    B    74.    A    75.    B    76.    C    

77.    D    78.    C    79.    D    80.    D    81.    A    82.    D    83.    C    84.    D 85.    A    86.    A    87.    C    88.    C    

89.    B    90.    B    91.    C    92.    B    93.    C    94.    B    95.    D    96.    A    97.    C    98.    A    99.    C    100.    A