Acrosomal reactions

Definition

The acrosomal reaction is a process that occurs when the sperm comes into contact with the egg's outer layer, facilitating fertilization. It involves the release of enzymes from the acrosome to penetrate the egg’s protective barriers.

5 Must Know Facts For Your Next Test

1. The acrosomal reaction is triggered when the sperm binds to receptors on the zona pellucida of the egg.
2. Enzymes such as hyaluronidase and acrosin are released during this reaction to digest a path through the zona pellucida.
3. The successful completion of the acrosomal reaction allows for sperm fusion with the egg membrane.
4. A failure in the acrosomal reaction can result in failed fertilization, affecting fertility.
5. This process is species-specific, meaning that sperm typically only reacts with eggs of its own species.

Review Questions

Related terms

Capacitation:

A maturation process that sperm must undergo to become capable of undergoing an acrosomal reaction and fertilizing an egg.

Zona Pellucida: The glycoprotein layer surrounding an oocyte, which plays a critical role in species-specific sperm binding and penetration during fertilization.

Cortical Reaction:

A process after sperm entry into an egg that prevents polyspermy by hardening the zona pellucida and making it impenetrable to additional sperms.