Question

Arrange the following stages of fertilisation and early development into a proper sequence.
I. Sperm entry
II. Acrosomal reaction
III. Karyogamy
IV. Capacitation
V. Cortical reaction

• A. I, III, II, IV, V
• B. III, V, I, IV, II
• C. IV, II, V, I, III
• D. V, I, IV, II, III

Answer 1

The correct option is A I, III, II, IV, V

Fertilization can be described as the following steps:

1. Sperm Capacitation.

2. Sperm-Zona Pellucida Binding.

3. The Acrosome Reaction.

4. Penetration of the Zona Pellucida.

5. Sperm-Oocyte Binding.

6. Egg Activation and the Cortical Reaction.

7. The Zona Reaction.

8. Post-fertilization Events.

So, the correct option is 'I, III, II, IV, V'.