Each members of JAK family of kinases contains:

An N-terminal domain that binds to the receptor

A C-terminal kinase domain 

A middle pseudokinase domain

TLS Online TPP Program

#Id: 7575

#Unit 5. Developmental Biology

The capacities the sperm gain are those for:

recognizing the cues that will guide them to the egg

undergoing the acrosome reaction

fusing with the egg cell membrane

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#Id: 7576

#Unit 5. Developmental Biology

Sperm that are not capacitated are “held up” in the cumulus matrix and are unable to reach the egg

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#Id: 7577

#Unit 5. Developmental Biology

Capacitation is a transient event, and sperm are given a relatively brief window of competence during which they can successfully fertilize the egg. As the sperm reach the ampulla, they acquire competence—but they lose it if they stay around too long

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#Id: 7578

#Unit 5. Developmental Biology

The molecular processes of capacitation prepare the sperm for the acrosome reaction and enable the sperm to become hyperactive

TLS Online TPP Program

#Id: 7579

#Unit 5. Developmental Biology

Capacitation

The sperm cell membrane

is altered by the removal of

cholesterol by albumin proteins in the female reproductive tract

TLS Online TPP Program

#Id: 7580

#Unit 5. Developmental Biology

The cholesterol efflux from the sperm cell membrane is thought to change the location of its “lipid rafts,” contain receptor proteins that can bind the zona pellucida and participate in the acrosome reaction