- Created by: emily.w.7
- Created on: 24-01-19 09:15
- In the nucleas the transcription of DNA into mRNA happens.
- the mRNA then leaves the nucleas via the nuclear envolope.
- the protien made on ribosomes then enter the Rer.
- protien moves through the er assumng 3d shape en route.
- Vesicles pinched off the Rer contain the protien
- theese vesicles then move and fuse to the flattened sacs of the golgi appuratus.
- the proteins are modified and packed @ golgi
- vesicles pinch off the golgi contain the modified protein
- the vesicle fuses with the cell surface membrane releasing protein such as exrtacellular enzymes via endocytosis
transcription, Mrna leaves, Rer, through er, vesicles, fuse golgi apuratus, mod & pakced, fuse with the C.S.M.
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- Day 14 egg released from the follicle in the ovary (ovulation)
- egg travels along the fallopian tube
- sperm approches the egg in the fallopian tube
- chemicals from the follicle cells trigger acrosome reaction.
- acrosome swells fusing sperm to cell membrane of the egg
- hydrolitic/acrosome enzymes are released and hydrolise the follicle cells and zona pellucida.
- sperms fuses with the egg cell membrane.
- sperm enters the egg. The tail doesnt enter.
- cortical granuales and cause the zona pellucida to thicken/ harden = cortical reaction, preventing polyspermy.
- nuclei of the egg/ovum and sperm fuse, called zygotes.
- fetrilisation has now occured.
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