Question

At the time of birth, the ovum is in the form of
A. Oogonia
B. Primary oocyte
C. Secondary oocyte
D. Egg

Answer 1

Hint: Ovum is the female reproductive cells released from the ovaries which are capable of fertilising with a sperm cell. It carries the set of chromosomes which is contributed by the female during fertilisation.

Complete Answer:
The process of differentiation of ovum is called oogenesis.
- The first step of oogenesis is development of primary oocytes. The oogonia which is formed during the embryo stage are transformed into the primary oocytes by the process called oocytogenesis. It is completed before the birth or shortly after birth. It is a meiotic division.
- After the birth by the primary oocytes develops into ootids by the process of meiosis.It occurs at the time of puberty.
- The ootids form mature ovum or the secondary oocytes by the process of meiosis.
- The eggs are released by the process of ovulation. These eggs are capable of fertilisation.
Oogonium —> Primary Oocyte —> Secondary oocyte —> Ovum

Thus the correct answer is (B). At the time of birth, the ovum is in the form of primary oocyte.

Note: At the time of birth, the female ovaries contain around 1-2 million primary oocytes. The females are not capable of making eggs. These eggs are released at the time of puberty once in a month by the process called ovulation.