Double Fertilisation

Q.

Identify the correct sequence of events in double fertilisation.

1. Both A & B

2. Endosperm - embryo - primary Endosperm cell

3. Egg cell - zygote - embryo

4. Central cell - primary endosperm cell - endosperm

Q. Endosperm of seed develops from

1. diploid nucleus
2. polyploidy nucleus
3. haploid nucleus
4. triploid nucleus

Q. Match the pairs.

1. 
2. Arthropod
3. Aves
4. Reptile
5. 
6. Amphibia
7. 
8. 

Q. [A] The given figure shows the L.S. of an ovary at the time of fertilisation. Study the figure and answer the questions based on it.

(i) Label parts 1-10.
(ii) Define triple fusion.
(iii)What happens to part 6 and 7?
[B]
(i) What are the disadvantages of self-pollination?
(ii) Why is the fertilisation process in Angiosperms known as double fertilization?

Q. Calculate the number of chromosomes involved in double fertilisation of a maize plant, given the diploid chromosome number of maize is 20.

1. 70
2. 100
3. 50
4. 80

Q. Name the process that has been shown in the given image. Identify the fate of A and B in the process, and their ploidy composition.

1. Process: Fertilisation; A:- Central cell (2n); B: Synergid cells (2n)
2. Process: Germination; A: Zygote (2n); B: Endosperm (3n)
3. Process: Double fertilisation; A: Endosperm (3n); B: Zygote (2n)
4. Process: Fertilisation; A: Endosperm (2n); B: Egg cell (2n)

Q. Each pollen grain produces ______ male gametes.

1. Three
2. Two
3. Four
4. One

Q. The role of double fertilisation in angiosperms is to produce

1. cotyledons
2. endocarp
3. endosperm
4. hormones

Q. [A] The given figure shows the L.S. of an ovary at the time of fertilisation. Study the figure and answer the questions based on it.

(i) Label parts 1-10.
(ii) Define triple fusion.
(iii)What happens to part 6 and 7?
[B]
(i) What are the disadvantages of self-pollination?
(ii) Why is the fertilisation process in Angiosperms known as double fertilization?

Q. Important terrestrial adaptations that evolved exclusively in seed plants include all of the following characteristics except:

1. Pollination by wind or animal instead of swimming sperm
2. Transport of water through vascular tissue
3. Retention of the gametophytic plant within the sporophyte
4. Protection and nourishment of the embryo within the seed