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The answer is (c) Bat

• Pollination occurs through bats is called chiropterophily and flower is called chiropterophilous flower. 
• It is seen in flowers of Adansonia, Kigellia, Bauhinia, Anthocephalus etc.
• Adaptations in chiropterophilous flower.
• Flowers are large, dull coloured and have a strong scent like that of rotting fruits.

The answer is (a) Viola

Shoot system is formed by the plumule after germination of seeds.

During development, the embryo derives nourishment from the endosperm.

• Adaptation for cross-pollination is unisexuality and dichogamy. 
• In unisexual flowers, stamens and carpels are borne in different flowers either on the same plant or in flowers borne on separate plants ensuring cross-pollination. 
• In dichogamy, stamens and carpels in a flower do not mature at the same time and hence selfpollination is eliminated. 
• When pollen grains are transferred to the stigma of the flower on the different plant it is called Crosspollination or Allogamy. 

Two adaptations for cross-pollination: 

Xenogamy: Pollen grains of a flower is transferred to the stigma of a different flower on a different plant of same species. 

 Hybridism: Pollen grains of a flower is transferred to the stigma of a flower of a plant of different species.

• Polar nuclei (n)
• Primary endosperm nucleus (3n)
• Definitive nucleus (2n)
• Synergids (n)
• Nucellus (2n)

• In albuminous seeds, the endosperm tissue persists in the mature seed and is used up at the time of germination. 
• In these seeds, the embryo is minute, whereas in exalbuminous seeds the endosperm is used up during embryo development and the mature seed does not contain endosperm. 
• In such seeds, the embryo is bulky and food is stored in cotyledons of the seed.

• The wall of the pollen grain has deposition of a complex compound known as sporopollenin. 
• This substance is waterproof, resistant to microbial decay, and is very stiff.
• This hardshell ensures that the tender cell inside has a strong chance of survival.

• After pollination and fertilization, the ovules develop into seed and the ovary is transformed into fruit. 
• The wall of ovary forms the fruit wall and it is called pericarp whereas perisperm is the remains of nucellus in the form of a thin and papery membrane in the seed in some cases. (Example: Black pepper).

After a successful act of fertilization and double fertilization, each ovule is transformed into the seed. The parts of ovule undergo morphological changes as follows: 

• Funicle – Stalk of seed 
• Micropyle – Gets sealed .
• Nucellus – Degenerates in most cases.
• Integuments – Seed coat, (outer integument-Testa and inner integument-Tegmen).
• Fertilized egg – Embryo.
• Primary endosperm nucleus – Endosperm (Present in albuminous seeds and not in exalbuminous seeds).
• Antipodals and synergids – Degenerate.

Wind pollinated flowers produce pollen in large amount and the pollen is small, dry, light and smooth so that they can be blown by the wind to a great distance.

The suspensor pushes the developing embryo in the food-laden endosperm and thus ensures proper development of an embryo. The extreme micropylar cell of suspensor becomes enlarged and also functions as haustorium. The lowermost cell of suspensor, in contact with the developing embryo, is called hypophysis and gives rise to the tip of radicle.

The result of the triple fusion is the formation of a triploid nucleus called a primary endosperm nucleus. This nucleus by repeated mitotic divisions gives rise to the formation of the endosperm. This endosperm provides nourishment to the developing embryo. It is a unique event in the entire living world where a triploid tissue nourishes a diploid tissue, and also that the nourishing tissue has genome both of maternal as well as paternal parents

Out of two male gametes released from the pollen tube, one fuses with the egg cell. This act is called fertilization. In angiosperms, this is necessarily followed by fusion of the second male gamete with the product of a fusion of two polar nuclei i.e. with the secondary nucleus. This is called triple fusion and thus both the male gametes participate in the act of fertilization. This is called double fertilization and is a unique feature of angiosperms. After a successful act of fertilization and double fertilization, each ovule is transformed into the seed. 

The parts of ovule undergo morphological changes as follows: 

• Funicle – Stalk of seed
• Micropyle – Gets sealed
• ucellus – Degenerates in most cases.
• Integuments – Seed coat, (outer integument-Testa and inner integument Tegmen).
• Fertilized egg – Embryo 
• Primary endosperm nucleus – Endosperm (Present in albuminous seeds and not in exalbuminous seeds). 
• Antipodals and synergids – Degenerate.

Transfer of pollen from the anther to the stigma of the flower is called pollination. It can be of two types: 

•  Self-pollination
• Cross-pollination 

In cross-pollination, pollen grains are transferred by some agency from the flower to the stigma of the flower on a different plant of the same species or a different species. To eliminate self-pollination and to promote cross-pollination, flowers develop following adaptations:

1. Self sterility or incompatibility 

2. Unisexuality or Decline 

3. Dichogamy 

4. Herkogamy 

5. Heterostyly

1. Incompatibility: Failure of germination of pollen on the stigma of same plant or failure of fusion between the functional male gamete with the mature and functional egg is called as incompatibility or self sterility. This may be physiological or morphological and is considered as an adaptation to eliminate self-pollination and promote crosspollination 

2. Development of seed: After successful fertilization, the ovule is transformed into seed by several morphological and physiological changes. After a successful act of fertilization and double fertilization, each ovule is transformed into the seed. The parts of ovule undergo morphological changes as follows: 

• Funicle – Stalk of seed 
• Micropyle – Gets sealed
• Nucellus – Degenerates in most cases.
• Integuments – Seed coat, (outer integument-Testa and inner integument-Tegmen).
• Fertilized egg – Embryo
• rimary endosperm nucleus – Endosperm (Present in albuminous seeds and not in exalbuminous seeds).
• Antipodals and synergids – Degenerate. 

3. Development of fruit: The stimulus of pollination and fertilization induces several changes in the ovary and it is transformed into fruit. The ovary wall forms the fruit wall called pericarp and it encloses the seeds formed by the transformation of ovules.

4. Alternation of generation: In all sexually reproducing plants, there are two phases or generations in the life cycle. These two generations are haploid gametophytic (n) and diploid sporophytic (2n) phase and the two occur alternately. “This is called alternation of a generation”. In angiosperms, the prominent phase is diploid sporophyte, differentiated into root, stem and leaves. It gives rise to haploid phase by meiotic division of microspore mother cells and megaspore mother cells. The gametophytic phase produces male gametes and egg cell which by syngamy bring the diploid phase into existence. Here the gametophytic phase is short-lived and is completely dependent on the diploid sporophytic phase.

The answer is (c) Nawaschin

• Double fertilization was discovered by Nawaschin in Fritillaria and Lilium in the year 1898. 
• During double fertilization, the fusion of one sperm with the egg cell forms the embryo and that of the other sperm with a polar nucleus gives rise to the endosperm.