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In: Biology

Which of the following statements about heterotrimeric G proteins is FALSE. Upon activation by a G-protein...

Which of the following statements about heterotrimeric G proteins is FALSE.

Upon activation by a G-protein coupled receptor, the G-protein usually breaks into two complexes, each of which can activate target proteins.

The α subunit is bound to GTP when the protein is in the inactive state

The activated a subunit switches itself off by hydrolyzing its bound GTP

G-proteins can activate membrane-bound enzymes and ion channels

Once activated by a receptor, the α subunit can dissociate from the receptor

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