The following are true about G proteins:
a. they are first messengers
b. when activated, the alpha subunit exchange GDP for GTP
c. they are transmembrane signal receptor molecules
d. vibrio cholerae secrets an exotoxin which makes G-proteins resistant to inactivation
a. they are first messengers
b. when activated, the alpha subunit exchange GDP for GTP
c. they are transmembrane signal receptor molecules
d. vibrio cholerae secrets an exotoxin which makes G-proteins resistant to inactivation