Question

Female gametophyte of angiosperm is

• A. 7 celled
• B. 8 celled
• C. 11 celled
• D. 5 celled

Answer 1

The correct option is A 7 celled

In angiosperm, the female gametophyte develops from a single megaspore. This megaspore undergoes three successive mitotic divisions to form eight nucleated embryo sac. Two nuclei are formed in the first mitotic division in the megaspore. The two nuclei move to opposite poles. These nuclei divide and re-divide at their ends to form eight nucleated stage. Each end has four nuclei. Three nuclei differentiate into two synergids and one egg cell at the micropylar end. At the chalazal end, three nuclei differentiate as antipodal cells. The remaining two nuclei, one of the micropylar end and other at the chalazal end migrate towards the centre and fuse. Hence, female gametophyte of angiosperm is 7 celled but 8 nucleated structure.

Thus, the correct answer is option A.