The hormones secreted by the posterior pituitary gland (neurohypophysis) are arginine vasopressin (AVP) and oxytocin

TLS Online TPP Program

#Id: 7584

#Unit 5. Developmental Biology

Calcium and bicarbonate ions are critical in activating cAMP production and in facilitating the membrane fusion events of the acrosome reaction

TLS Online TPP Program

#Id: 7585

#Unit 5. Developmental Biology

The influx of bicarbonate ions (and possibly other ions) alkalinizes the sperm, raising its pH. This will be critical in the subsequent activation of calcium channels

TLS Online TPP Program

#Id: 7586

#Unit 5. Developmental Biology

During capacitation, 

cAMP formation, protein

phosphorylation occurs. 

One of these proteins is Izumo, which is critical in sperm-egg fusion

TLS Online TPP Program

#Id: 7587

#Unit 5. Developmental Biology

Connection between sperm translocation

and capacitationbefore entering the ampulla of the oviduct, the uncapacitated sperm bindactively to the membranes of the oviduct cells in the the isthmus) & this bindingis temporary and appears to be broken when the sperm become capacitated

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#Id: 7588

#Unit 5. Developmental Biology

Toward the end of capacitation, sperm become hyperactivated—The symmetrical beating of the flagellum is changed into a rapid asynchronous beat with a higher degree of bending. 

TLS Online TPP Program

#Id: 7589

#Unit 5. Developmental Biology

Hyperactivation mediated by the opening of the sperm specific calcium channels, the CatSper proteins, in the sperm tail.