Chapter 31, Problem 1TY

Where do the pollen grams of flowering plants develop?

1. in the anthers of a flower
2. in the carpels of a flower
3. while being dispersed by wind, water, or animals
4. within ovules
5. within pistils

Summary Introduction

Introduction:

Flowering plants reproduce sexually. Sexual reproduction in plants involves a male portion and a female portion. Pollen grains represent the male portion of sexual reproduction in flowering plants. Pollen grains are microscopic in structure. It reaches the female portion either by swirling with the wind or by attaching itself to the sticky legs of the insects which visit the other flowers of same or different species

Answer to Problem 1TY

The correct answer is option (a) in the anthers of the flowers.

Explanation of Solution

Explanation/justification for the correct answer:

Option (a) in the anthers of the flowers. The anther is a part of the male reproductive whorl of the plant known as Androecium. It is usually bilobed with two chambers known as pollen-sacs, where pollen grains are produced.

Explanation for incorrect answer:

Option (b) in the carpels of the flower. Carpels are the unit of the female reproductive system which receives the pollen grains for fertilization. Hence, it has no role in the production of pollen grains.

Option (c) while being dispersed by wind, water or animals. Dispersion is a process associated with the transfer of seeds to faraway places so that they can get proper sunlight air and water to germinate. Pollen grains can move to other places with the help of air, water or animals, but dispersion is a process that follows after pollen formation. So this is not a correct option.

Option (d) within ovules. Ovules too are a part of the female reproductive organ or Gynoecium, which is a completely different whorl of the plant-associated with sexual reproduction in plants. Within ovule, cells divide to produce egg and other cells which are fertilized by the sperm cell present in the pollen grains. Thus we see that ovule mainly takes part in Fertilisation which comes much late after pollen formation. Thus this option is incorrect too.

Option (e) within pistils. The pistil is a part of the Female reproductive whorl of the plant It is often used to refer one carpel or many carpels fused together. Hence, this option is also incorrect as its role comes after pollen grain formation.

Conclusion

Pollen grains are the male portion of sexual reproduction in flowering plants. Hence, the correct answer is option (a) in the anthers of flowers.