During the process of egg fertilization, a series of complex and coordinated events occur to ensure successful reproduction. The initial fusion of the egg and sperm triggers a significant rise in calcium levels within the egg, which in turn stimulates the release of cortical granules.
To restart meiosis, the calcium signal mediates dramatic rearrangement of egg surface including :
egg activation
>Initiated by the fusing of egg and sperm
>Causes rise in Ca2+
>Stimulate cortical granules to release their contents outside the egg
>Cause formation of fertilization envelope (to slow block polyspermy)
Once egg activated,egg will resume and complete meiosis ii with release of 2nd polar body
Stages of egg fertilization
5) Cortical changes takes place (gray crescent in amphibians)
4)Vitelline layer strengthen and thickens
3)Formation of fertilization membrane
2) Sperm is drawn into egg cytoplasm
1) Egg membrane wraps microvilli around sperm head
Main topic
Initiated by
Independent Fertilization
Fertilization
Meaning
Process of interaction between sperm and egg at fertilization which stimulates the eggs to begin development
