What happens to glucose during glycolysis?

Question

What happens to glucose during glycolysis??  
A. Its energy is entirely lost.  
B. It splits into molecules of pyruvic acid.  
C. It is stored in NADH.  
D. It joins with molecules of citric acid.

Accepted Answer

Correct Answer: (B)It splits into molecules of pyruvic acid.. 
Rationale: Glucose splits into two molecules of pyruvic acid during glycolysis.Glycolysis is the first stage of cellular respiration and takes place in the cytoplasm of the cell. In this process, one molecule of glucose (which has 6 carbon atoms) is broken down through a series of enzyme-controlled reactions into two molecules of pyruvic acid (each with 3 carbon atoms). During this breakdown, some of the chemical energy stored in glucose is transferred to ATP and NADH, which the cell can later use to produce more energy. This step is essential because it prepares glucose for further energy extraction in the mitochondria.A) Its energy is entirely lostThis is incorrect. Although some energy is released as heat, most of the energy from glucose is conserved in chemical form. Glycolysis produces a net gain of 2 ATP molecules and 2 NADH molecules, which store energy for later use in the electron transport chain. Therefore, glucose’s energy is not entirely lost.B) It splits into molecules of pyruvic acidThis is correct. During glycolysis, one glucose molecule is divided into two molecules of pyruvic acid (also called pyruvate). This splitting is the defining outcome of glycolysis and allows the cell to continue extracting energy from glucose in later stages of respiration.C) It is stored in NADHThis is incorrect. NADH does not store glucose. Instead, NADH is a carrier molecule that stores high-energy electrons and hydrogen ions released during glucose breakdown. The glucose molecule itself is chemically converted into pyruvic acid.D) It joins with molecules of citric acidThis is incorrect. Citric acid is formed later during the Krebs cycle when acetyl-CoA (derived from pyruvic acid) combines with oxaloacetate. Glucose does not directly join with citric acid during glycolysis.ConclusionDuring glycolysis, glucose is broken down into two molecules of pyruvic acid while releasing energy stored in ATP and NADH. Therefore, the correct answer is B) It splits into molecules of pyruvic acid.

What happens to glucose during glycolysis?

A
Its energy is entirely lost.

B
It splits into molecules of pyruvic acid.

C
It is stored in NADH.

D
It joins with molecules of citric acid.

Glucose splits into two molecules of pyruvic acid during glycolysis.

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What happens to glucose during glycolysis?

A Its energy is entirely lost. B It splits into molecules of pyruvic acid. C It is stored in NADH. D It joins with molecules of citric acid.

Glucose splits into two molecules of pyruvic acid during glycolysis.

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A
Its energy is entirely lost.

B
It splits into molecules of pyruvic acid.

C
It is stored in NADH.

D
It joins with molecules of citric acid.