Question

Name the parts marked as ‘A’ and ‘B’ in the given diagram. Write in detail the changes that take place in a flower when the product of ‘B’ reaches ‘A’ till a fruit is formed.

Answer 1

1. In the given diagram of a flower, ‘A’ is the stigma. The part of the pistil where pollen is received during pollination.
2. In the given diagram of a flower, ‘A’ is the anther. The anther is the part of the stamen which produces and releases pollen.

Changes in a flower after the pollen reaches the stigma:

1. Pollination: A stigma (A) of a flower receives pollen from the anther (B).
2. Germination of pollen: A pollen tube is formed when the pollen grain germinates on the stigma.
3. Growth of pollen tube: The pollen tube descends to the ovary via the style.
4. Fertilisation: Fertilisation occurs when the male gamete (sperm cell) passes through the pollen tube and fuses with the female gamete (egg) in the ovule in the ovary.
5. Formation of zygote: The fertillised eggs are developed into a zygote.
6. Development of the fruit: The ovule turns into seeds, and the ovary becomes a fruit.