In glycolysis, glucose is broken down through series of reactions in the presence of enzyme and absence of oxygen to produce

Analyze the question: It asks for the end products of glycolysis, which takes place without oxygen and is controlled by enzymes.

Concept: Glycolysis is the first stage of respiration. It happens in the cytoplasm of the cell and does not need oxygen. One molecule of glucose (6 carbons) is broken down in stages into two molecules of pyruvic acid (pyruvate, 3 carbons).

Step-by-step solution:

1. Glucose is phosphorylated using 2 ATP. This is the "investment" phase, and it produces phosphorylated glucose, which is only an intermediate.
2. The 6-carbon sugar splits into two 3-carbon molecules.
3. These are converted in a series of enzyme-controlled steps into 2 pyruvic acid molecules.
4. In the process, 4 ATP are produced. Subtracting the 2 ATP used gives a net gain of 2 ATP. Also, 2 NADH are formed.

Checking each option:

• A. Acetyl-coenzyme A + ATP: Acetyl-CoA forms after glycolysis, when pyruvate enters the mitochondria (the link reaction). It is not a product of glycolysis.
• B. Phosphorylated glucose: This is only an early intermediate, not the final product.
• C. Pyruvic acid + ATP: Correct. These are the main end products of glycolysis.
• D. Amino acid: Not related to glycolysis.

Answer: C. Pyruvic acid + ATP

Exam tip: Remember "Glycolysis = Glucose → 2 Pyruvate + 2 ATP (net)". Where it happens is the cytoplasm, and it needs no oxygen. If oxygen is present, pyruvate goes on to the Krebs cycle. If oxygen is absent, it becomes lactic acid (in animals) or ethanol and CO₂ (in yeast).