The capacitated sperm are also able to detect and respond to picomolar amounts of the hormone progesterone, which is secreted by the cumulus cells surrounding the egg

TLS Online TPP Program

#Id: 4035

#Unit 7. System Physiology – Animal

Increase in intracellular cAMP facilitates the opening of L channels, increasing ICa and the rapidity of the depolarization phase of the impulse.

TLS Online TPP Program

#Id: 4036

#Unit 7. System Physiology – Animal

When the cholinergic vagal fibers to nodal tissue are stimulated, the membrane becomes hyperpolarized and the slope of the prepotentials is decreased

TLS Online TPP Program

#Id: 4037

#Unit 7. System Physiology – Animal

Acetylcholine (ACh), released from parasympathetic nerve fibers, activates muscarinic (M2) receptors in the SA node.

TLS Online TPP Program

#Id: 4038

#Unit 7. System Physiology – Animal

activation of the M2 receptors decreases cyclic adenosine 3′,5′-monophosphate (cAMP) in the cells, and this slows the opening of Ca 2+ channels.

TLS Online TPP Program

#Id: 4039

#Unit 7. System Physiology – Animal

βγ subunit of a G protein, open a special set of K + channels. The resulting IKAch slows the depolarizing effect of Ih .

TLS Online TPP Program

#Id: 4040

#Unit 7. System Physiology – Animal