Fertilization Flashcards
What is the optimal time to inseminate?
6 or more hours before ovulation.
Why is 6 hours pre-ovulation the optimal time?
6 hours is the minimum required time for the capacitation of fresh sperm.
How is frozen sperm different from fresh sperm in terms of capacitation?
Frozen sperm is partially capacitated when thawed.
What is capacitation?
The changes within sperm that confer upon it the ability to acrosome react in response to the appropriate stimulus(binding to the zona pellucida).
Where does capacitation begin and end for anterior vagina deposition?
Begins in the cervix and ends in the isthmus.
Where does capacitation begin and end for cervical/uterine deposition?
Begins in the uterus and ends in the isthmus.
Is capacitation reversible?
Yes.
Does capacitation change sperm morphology?
No.
What motility change occurs during capacitation?
Hyperactivation due to increased cAMP and power output.
What is the purpose of hyperactivation?
To increase the chance of the sperm meeting the oocyte due to the sperm moving in a non-linear fashion.
What are the steps of fertilization?
- Hyperactive motility.
- BINDING of the sperm to the zona pellucida.
- Acrosome reaction.
- Sperm penetration through the zona pellucida.
- Sperm-oolema (oocyte membrane) FUSION.
- Oocyte engulfs sperm.
- Decondensation of the sperm nucleus.
- Formation of the male pronucleus.
What is the biochemical classification of zona proteins?
Glycoproteins.
How many zona proteins do most animals have?
Most have 3, but some have 4.
What is the function of ZP1 and ZP2?
To maintain the structural integrity of the zona pelluicida.
What is the function of ZP3?
An extramembrane receptor for sperm.