There are about 90 million rod cells in the human retina, and each contains about 4x107 molecules of rhodopsin that are very densely packed in the membrane disks.

TLS Online TPP Program

#Id: 9705

#XL - T Zoology

The receptors for yeast α and a mating factors are coupled to the same trimeric G protein.

TLS Online TPP Program

#Id: 9706

#XL - T Zoology

Ligand binding to either of the two yeast pheromone GPCRs triggers the exchange of GTP for GDP on the Gα subunit and dissociation of Gα∙GTP from the Gβγ complex.

TLS Online TPP Program

#Id: 9707

#XL - T Zoology

Ligand binding and dissociation of the G protein subunits, the membrane-tethered Gβγ subunit binds the Ste5.

TLS Online TPP Program

#Id: 9708

#XL - T Zoology

Ste5 acts as a scaffold for assembling other components in the cascade Ste11, Ste7, and Fus3.

TLS Online TPP Program

#Id: 9709

#XL - T Zoology

Gβγ activates Cdc24, a GEF for Cdc42

TLS Online TPP Program

#Id: 9710

#XL - T Zoology

Cdc24 = SOS

Cdc42 = Ras