Question

The pollen grain is?
A: An immature male gametophyte
B: A mature male gametophyte
C: Partially developed male gametophyte
D: Both (A) and (C)

Answer 1

Hint: Pollen grains are the tiny structure present in the flower of different shapes and sizes. Each pollen grain contains a vegetative or non – reproductive cells and generative or reproductive cells. The generative cell undergoes mitosis to form two male gametes. Each pollen grain is a single cell containing two male gametes. Both the male gametes are involved in the process of fertilisation.

Complete answer:
The microsporangia of a male cone produce the pollen in gymnosperms and angiosperms flowers produce the anther.
Pollen grains come in different shapes, size and characteristics.
Each pollen grain is a single cell containing two male gametes.
 Each pollen grain consists of vegetative cells and generative cells.
 The generative cells produce male gametes and the vegetative cells produce pollen tubes.
The unicellular microspores develop into mature microgametophytes containing gametes during microgametogenesis by the process of mitotic cell division. So, the pollen is an immature or partially developed male gametophyte.
Similarly, the unicellular microspore produces male gametes and develops into mature microgametophyte by the process of mitotic cell division.
Hence, the pollen grains are immature male gametophyte and partially developed male gametophyte.

Hence, the correct option is D.

Additional Information :
In the process of reproduction in plants and animals, pollen grains play the role of the male.
These minute bodies with the help of air and legs of insects mate with the female part of the plants and this process is called fertilisation.
This pollen plays an important role in the process of fertilisation.
The other name of pollen is called microspores. The process of transfer of pollen grain from the anther to the stigma is called pollination.

Note:
Malarial parasite has two hosts to complete its life cycle. Human beings are considered as intermediate hosts while the female Anopheles mosquito serves as vector host. To prevent contaminated food and water diseases freshwater and food should be taken. To control infectious disease use of vaccines and immunization programs is a necessary step.