Question

Coenzymes "carry" or "hold onto" something used in a metabolic reaction. Coenzyme-A plays an important role in the TCA cycle. In this example, what does this coenzyme "carry" into the reaction______________.

Answer 1

Coenzyme A (CoA) carries the two-carbon acetyl group into the TCA cycle, where it participates in a series of reactions that eventually oxidize the acetyl group to carbon dioxide and generate ATP, NADH, and FADH2.

Step-by-step explanation:

In the context of the TCA cycle also known as the Krebs cycle or citric acid cycle, Coenzyme A (CoA) plays a crucial role. It is responsible for transporting the two-carbon molecule acetyl group into the reaction. After glycolysis, pyruvate is oxidized to form an acetyl group which then, via a transition reaction, gets attached to CoA to form acetyl CoA. The acetyl CoA then enters the TCA cycle, and the acetyl group is eventually oxidized to release energy in the form of ATP, NADH, and FADH2. The carbon atoms are released as CO2.

The formation of acetyl CoA from pyruvate and its subsequent introduction into the citric acid cycle constitutes a vital transition in cellular respiration. This process involves not only the transfer of the acetyl group to CoA but also the reduction of NAD+ to NADH, which captures high-energy electrons for use in the electron transport chain.

Coenzyme A, derived from vitamin B5, acts as the agent for transfer of acetyl groups (CH3CO-) in various metabolic reactions, demonstrating its pivotal role in cellular metabolism.

Answer 2

Acetyl group

Step-by-step explanation:

The coenzyme A is involved in various metabolic reactions; it carries acetyl group in the form of acetyl CoA into the TCA cycle which is further oxidized to produce water, carbon dioxide and energy in the form of Adenosine triphosphate (ATP) and guanosine triphosphate (GTP).

Acetyl CoA is derived from the oxidation of fats, proteins and carbohydrates.