Reeja, a science student, observed the structure of mature embryo sac comprising antipodals, central cells and egg apparatus. Explain each one of them.

In mature embryo sac, the central cell is

Raman is learning the post fertilization changes of an angiosperm embryo sac with the help of slides. He identified the egg nucleus and polar nuclei in the central cell with the help of his teacher. Help raman by giving the changes that take place with egg nucleus and polar nuclei.

Commercial cells can be classified into primary cells and secondary cells. Explain them by giving one example each.

Raman is learning the post fertilization changes of an angiosperm embryo sac with the help of slides. He identified the egg nucleus and polar nuclei in the central cell with the help of his teacher. Name the other nuclei present in the embryo sac.

Read the following statements carefully and select the appropriate option given below. (i) The distal end of the filament is attached to the thalamus or the petal of the flower. (ii) The pollen grains represent the male sporophyte. (iii) The microsporangia develop further and become embryo sac. (iv) In over 60 per cent of naked seeded plant, pollen grains are shed at this 2-celled stage. (v) As anthers mature and dehydrate the microspores, dissociate from each other and develop into pollen grains.