类别 全部 - meiosis - fertilization

作者:nur mastura 10 年以前

1057

egg activation

egg activation

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