Identify the statements which are correct with respect to fertilization.

(A) Sperm comes in contact with zona pellucida layer of the ovum
(B) Acrosome secretions help the sperm to pass through the cells of corona radiata
(C) Entry of sperm into the cytoplasm of ovum induces the completion of the meiotic division of the secondary oocyte
(D) Fertilization can occur if the ovum and sperms are transported simultaneously to the ampullary region

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) Sperm comes in contact with zona pellucida layer of the ovum .Correct — the sperm binds to glycoproteins of the zona pellucida, which triggers the acrosome reaction.

(B) Acrosome secretions help the sperm to pass through the cells of corona radiata. Incorrect — acrosome enzymes digest the zona pellucida, not the corona radiata. The sperm first penetrates the corona radiata with the help of hyaluronidase from sperm membrane, not acrosome enzymes.

(C) Entry of sperm into the cytoplasm of ovum induces the completion of the meiotic division of the secondary oocyte .Correct — the secondary oocyte (arrested in metaphase II) completes meiosis II only after sperm entry.

(D) Fertilization can occur if the ovum and sperms are transported simultaneously to the ampullary region .Correct — the ampullary–isthmic junction of the fallopian tube is the normal site of fertilization, and both gametes must meet there simultaneously.

Correct statements: (A), (C) and (D) only