Question

During the citric acid cycle, which is also known as the 15)_____ cycle, the two-carbon molecules fed into the cycle are broken down into more single-carbon molecules of 16)______.

Answer 1

During the citric acid cycle, which is also known as the 15)Tricarboxylic acid cycle or the Krebs cycle , the two-carbon molecules fed into the cycle are broken down into more single-carbon molecules of 16) Carbon dioxide.

Pyruvic Acid produced by glycolysis undergoes aerobic mitochondrial matrix through the TCA cycle. This cycle serves a common oxidative pathway for carbohydrates fats and proteins. Moreover, some intermediates of the TCA cycle are used in synthesizing important biomolecules such as glutamate and aspartate. oxidation the Before participating in the TCA cycle pyruvic acid enters the mitochondrion. Here it is decarboxylated and the remaining 2-carbon fragment is combined with a molecule of coenzyme A to form acetyl-CoA.
This reaction oxidative decarboxylation process and produces H+ ions and electrons along with carbon dioxide. During the process NAD+ is reduced to NADH+H+. B-oxidation of fatty acids also produces acetyl- CoA as the end product. Acetyl-CoA from both is up sources is condensed with oxaloacetic acid to form citric acid. Citric acid is oxidized step-wise by mitochondrial enzymes, evolving carbon dioxide. This finally regenerates oxaloacetic acid to complete the cycle. There are four steps of oxidation in this cycle, catalyzed by dehydrogenases (oxidoreductases) using NAD+ or FAD+ as the coenzyme. The coenzymes are consequently reduced to NADH+H and FADH, respectively. These transfer their electrons to the mitochondrial respiratory chain to get reoxidised. One molecule of GTP (ATP) is also produced for every molecule of citric acid oxidized.