Question

Three hypothetical phosphorylated compounds (A, B, and C) are involved in energy metabolism. Standard free energies of hydrolysis for A = 13.1 kcal/mol, for B = -2.7 kcal/mol, and for C = 6.7 kcal/mol.

What is the sequence in which these molecules could most exergonically phosphorylate?
A) A, B, C
B) A, C, B
C) B, C, A
D) C, B, A
E) C followed by A or B

Answer 1

The sequence in which the molecules could most exergonically phosphorylate is B, C, A, since compound B has the most exergonic reaction, followed by C and A.

Step-by-step explanation:

The question pertains to the sequence in which three hypothetical phosphorylated compounds (A, B, and C) involved in energy metabolism could most exergonically phosphorylate. The standard free energies of hydrolysis are given for each, and to determine the order, one must consider that a compound with a more negative free energy of hydrolysis can phosphorylate compounds with less negative (or more positive) free energy values.

Considering the energies provided (A = 13.1 kcal/mol, B = -2.7 kcal/mol, and C = 6.7 kcal/mol), we can see that B's energy is the most negative, followed by C, and then A. Therefore, the correct order of phosphorylation, from the compound with the most exergonic reaction to the least, would be B, then C, and finally A. Hence, the correct sequence is C) B, C, A.