A water-soluble hormone binds to its receptor on the plasma membrane. Arrange the events that follow in correct sequence.
(1) Alpha subunit-GTP complex alters cell activity
(2) GTP binds to the alpha subunit replacing GDP
(3) G-protein subunits separate from the receptor
(4) Alpha subunit separates from other two subunits
(5) G-protein subunits bind to the receptor
A) 5, 2, 3, 4, 1
B) 4, 2, 1, 3, 5
C) 5, 2, 1, 4, 3
D) 5, 4, 2, 1, 3
E) 3, 4, 1, 2, 5

Question

Quizplus · Accepted Answer

When a water-soluble hormone binds to its receptor, the G-protein subunits bind to the receptor (5), GTP replaces GDP on the alpha subunit (2), the G-protein subunits separate from the receptor (3), the alpha subunit separates from the other two subunits (4), and finally, the alpha subunit-GTP complex alters cell activity (1).

A Water-Soluble Hormone Binds to Its Receptor on the Plasma