Which of the following is a correct association?
a. adenylyl cyclase activity and the conversion of cAMP to AMP
b. GTPase activity and hydrolysis of GTP to GDP
c. kinase activity and the addition of a tyrosine
d. phosphodiesterase activity and the removal of phosphate groups

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

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