Question

what are prothaliial cells in a male gametophyte?

Answer 1

1. Microspores, which develop into male gametophytes, are un-winged in Cycas.

2. Only one prothallial cell is present in cycas.

3. In cycas the lone prothallial cell persists almost till the end of the male gametophyte development.

4. Pollination takes place at 3-celled stage in cycas, i.e. a prothallial cell, a generative cell and a tube cell.

5. Two motile male gametes, with several spiral bands of cilia, develop from generative cells in cycas.

6. Entire developmental process of male gametophyte in cycas completes within a few months.

7. Pollen tube grows sideways in cycas into the tissue of the nucellus.

8. In cycas the pollen tube is haustorial in function.