Question

Glucose is a large molecule that must be broken down into ______ before it can enter the mitochondria.

A. One molecule of pyruvate
B. Two molecules of kerb
C. Two molecules of pyruvate
D. One molecule of water

Answer 1

Glucose is broken down into two molecules of pyruvate during glycolysis, with a net yield of two ATP and two NADH molecules produced in the process.

Step-by-step explanation:

Glucose is a large molecule that must be broken down into two molecules of pyruvate before it can enter the mitochondria. This process is known as glycolysis, wherein one glucose molecule is converted into two 3-carbon pyruvate molecules, releasing some of the chemical energy stored in glucose.

During glycolysis, four ATP molecules and two NADH molecules are produced. Although four ATP molecules are formed, the net yield is two ATP molecules because two are consumed at the beginning of glycolysis. The generated pyruvate can then enter the mitochondria to be metabolically processed further either aerobically, via the Krebs cycle, or anaerobically.