In the Presence of Oxygen, the Three-Carbon Compound Pyruvate Can

question 36

Multiple Choice

In the presence of oxygen, the three-carbon compound pyruvate can be catabolized in the citric acid cycle. First, however, the pyruvate (1) loses a carbon, which is given off as a molecule of CO₂, (2) is oxidized to form a two-carbon compound called acetate, and (3) is bonded to coenzyme A. Which of the following sets of products result from these reactions?

• A) acetyl CoA, O₂, and ATP
• B) acetyl CoA, FADH₂, and CO₂
• C) acetyl CoA, NADH, and CO₂
• D) acetyl CoA, NAD⁺, ATP, and CO₂

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Definitions:

Trypsin

A digestive enzyme produced in the pancreas and secreted into the small intestine, where it breaks down proteins into smaller peptides.

Small Intestine

The part of the gastrointestinal tract between the stomach and large intestine, where most of the digestion and absorption of nutrients takes place.

Duodenum

The first part of the small intestine immediately beyond the stomach, where most chemical digestion takes place.

Jejunum

The mid-section of the small intestine in humans, where most of the digestion and absorption of nutrients occurs.