Question

What happens to other sperms entering the ovum cytoplasm?

Answer 1

Fertilization:

1. Sperm is a male reproductive cell
2. Fertilization is the process by which a haploid sperm (spermatozoan) and a haploid ovum fuse.
3. Once within the tubes, the sperm cells follow signals from the egg's supporting cells (cumulus cells) (a process known as chemotaxis).
4. The sperm cells undergo a number of biochemical and functional modifications along the journey.
5. These get the sperm cells ready for fertilisation.

Processes when sperms enter the ovum cytoplasm:

1. Sperm cells come into contact with a barrier of cumulus cells that surrounds the egg.
2. Sperm cells become hyperactive in order to get over this barrier.
3. The sperm cell next passes through the 'zona pellucida,' an extra layer of the egg.
4. To cross this barrier, sperm cells go through a process known as the acrosome response.
5. The sperm cell's acrosome secretes enzymes.
6. These enzymes dissolve the zona pellucida barrier, allowing sperm to enter the egg.
7. When the sperm cell's head is within the egg, the sperm's tail separates.
8. The zona pellucida becomes impenetrable to additional sperm cells at that point.
9. Any additional sperm that enters the ovum cytoplasm is destroyed in the cytoplasm.
10. The rapid block method involves a near-immediate shift in sodium ion permeability following engagement of the first sperm, depolarizing the oocyte plasma membrane and blocking subsequent sperm cell fusion.
11. Zonal inhibitory proteins allow any additionally connected sperm to be released and ruin the oocyte's sperm receptors, preventing any further sperm from adhering.