Question

In order for a G protein to be active:

Please choose the correct answer from the following choices, and then select the submit answer button.


-the alpha subunit must bind GTP and the beta and gamma subunits must separate from the alpha subunit.

-the beta and gamma subunits must separate from the alpha subunit.

-both the beta and gamma subunits must bind GTP.

-the alpha subunit must bind GTP.

Answer 1

A G protein is activated when its alpha subunit binds GTP and the beta and gamma subunits dissociate, enabling the alpha subunit to trigger cellular responses.

Step-by-step explanation:

For a G protein to be active, the alpha subunit must bind GTP and the beta and gamma subunits must separate from the alpha subunit. This activation occurs when a signaling molecule binds to a G-protein-coupled receptor, leading to the exchange of GDP for GTP on the alpha subunit. The dissociation of the beta and gamma subunits from the alpha subunit enables the latter to trigger a cellular response. The cycle is completed when the GTP on the alpha subunit is hydrolyzed back to GDP, causing the inactive alpha subunit to reassociate with the beta and gamma subunits.