Cells use a variety of metabolic pathways to construct ATP, but each concludes with the same step. Which of the following describes the final step by which ADP becomes ATP?
A)photosynthesis
B)phosphorylation
C)carbon fixation
D)electron transfer

Question

Quizplus · Accepted Answer

The final step by which ADP becomes ATP is through phosphorylation, the addition of a phosphate group to ADP by either substrate-level or oxidative phosphorylation. This reaction produces ATP, which is then used as an energy source for cellular processes. Photosynthesis is a metabolic pathway by which plants and some bacteria produce glucose using energy from sunlight. Carbon fixation is the process by which carbon from atmospheric CO2 is converted into organic molecules, and electron transfer is a broad term that encompasses a number of different metabolic pathways that involve the transfer of electrons between molecules.

Cells Use a Variety of Metabolic Pathways to Construct ATP