Select the statements which are true for oogenesis?

(A). Ovulation occurs at the secondary oocyte stage.
(B). Polar body is larger than the secondary oocyte.
(C). No more oogonia is formed after birth in the ovary.
(D). The sperm and the ovum nucleus fuse before the formation of the second polar body.

Choose the correct answer from the options given below:

(A), (C) and (D) only

The correct answer is Option (3) → (A), (C) and (D) only  

(A) Ovulation occurs at the secondary oocyte stage. True — Ovulation releases a secondary oocyte, which is arrested in metaphase II of meiosis and completes meiosis II only after fertilization.

(B) Polar body is larger than the secondary oocyte. False — The polar body is much smaller than the secondary oocyte. It contains very little cytoplasm and is a byproduct of unequal cell division.

(C) No more oogonia is formed after birth in the ovary. True — In human females, all oogonia are formed before birth. After birth, no new oogonia are produced.

(D) The sperm and the ovum nucleus fuse before the formation of the second polar body. True —Entry of sperm triggers the completion of meiosis II, leading to the formation of the second polar body, after which the male and female pronuclei fuse.

Final Answer: (A), (C) and (D) only