Question

Identify the correct ratio of male gametes, vegetative cells, generative cells and microspore mother cells produced in a microsporangium if 80 pollen grains are released from it.

Options

• 1:1:1:1

• 1:4:4:8

• 2:1:1:4

• 8:4:4:1

Answer 1

8:4:4:1

Explanation:

i. 1 microspore mother cell gives 4 pollen grains
→ 80 / 4 = 20 microspore mother cells

ii. Each pollen grain at maturity has 1 vegetative + 1 generative cell
→ 80 pollen grains will have 80 generative cells and 80 vegetative cells

iii. Mitotic division of each generative cell gives rise to 2 male gametes
→ 80 generative cells × 2 = 160 male gametes

iv. Ratio = 160: 80: 80: 20
= 8: 4: 4: 1