Question

Embryo sac of flowering plants develops from ?

• A. Zygote
• B. Megaspore
• C. Nucellus
• D. Embryo

Answer 1

The correct option is B Megaspore

Megaspore mother cell is developed inside the nucellus. It then undergoes meiotic division to form four haploid megaspores. Out of these four megaspores, three degenerate and only one remains functional. This functional megaspore then undergoes mitosis three times without cytoplasmic divisions which results in 8 nuclei in the megaspore. These 8 nuclei then get organized into egg apparatus (consisting of an egg cell and two synergids), a large central cell and three antipodal cells. This results in the formation of a 7-celled but 8-nucleate structure which is called the embro sac.

Hence, embryo sac of flowering plants develop from megapore.

So, the correct answer is B.