Question

Assertion: During fertilization, only the head of spermatozoa enters the egg.

Reason: If several spermatozoa hit the egg at the same time, all can enter the egg.

• A. Both the assertion and the reason are true and the reason is the correct explanation for the assertion.
• B. Both the assertion and the reason are true but the reason is not the correct explanation for the assertion.
• C. The assertion is true but the reason is false.
• D. The assertion is false but the reason is true.

Answer 1

The correct option is C

The assertion is true but the reason is false.

The correct option is (C).

Explanation of the assertion statement:

1. During fertilization only one sperm (spermatozoa) head enters the egg.
2. The sperm head contains the nucleus which has all the genetic information stored in the chomosomes.
3. That fuses with the egg nucleus and thus recombination happens and that leads to the formation of a zygote with a diploid chromosome number.
4. The acrosome (derived from the Golgi complex) present in the sperm pierces through the egg cell.
5. Hence, the assertion statement is correct.

Explanation of the reason statement:

1. Even if several spermatozoa hit the egg at the same time, only one can enter the egg (oocyte).
2. This is because after one sperm cell enters the egg cell polyspermic fertilization block the further oocyte sperm fusion.
3. Hence, the reason statement is incorrect.

Final answer:

The assertion is true but the reason is false.