A flower’s anthers are removed before it matures. Later, pollen from another plant. Class 9

A flower’s anthers are removed before it matures. Later, pollen from another plant. Class 9

Revise, Reflect, Refine (Page 225-226)

Question 1.

A flower’s anthers are removed before it matures. Later, pollen from another plant of the same species is dusted onto its stigma and seeds are produced. Which process has been ensured here? Class 9

(i) Self-pollination

(ii) Cross-pollination

(iii) Fertilisation

(iv) Tissue culture

Answer:

(ii) Cross-pollination

Explanation: Removing the anthers ensures that the flower cannot pollinate itself (self-pollination is prevented). When pollen from another plant of the same species is then placed on its stigma, pollen is transferred from one plant to another of the same species - this is exactly the definition of cross-pollination.

Question 2.

Arrange the following stages of sexual reproduction in plants in the correct order: Class 9

(i) Pollen germination on stigma

(ii) Fertilisation

(iii) Pollination

(iv) Formation of zygote

Answer:

(iii) Pollination → (i) Pollen germination on stigma → (ii) Fertilisation → (iv) Formation of zygote

Explanation: First, pollen is transferred to the stigma (pollination). Then the pollen grain germinates on the stigma and produces a pollen tube. The pollen tube grows down through the style into the ovary (germination). The male gamete travels through the tube to the ovule and fuses with the egg cell (fertilisation). This fusion produces the zygote (formation of zygote).