NEET Biology: Cellular respiration-glycolysis Practice Questions
15 free multiple-choice questions on Cellular respiration-glycolysis (Respiration) for NEET Biology, each with the correct answer and a step-by-step explanation. Attempt a question, then reveal the solution to check your reasoning.
Practice thousands more NEET questions in the app →Q1. What is the immediate end product of the anaerobic breakdown of pyruvate in the absence of oxygen (fermentation)?
Show answer & explanation
Correct answer: C — Lactate
When oxygen is scarce, pyruvate is converted into lactate (lactic acid) to regenerate NAD+ for continued glycolysis.
Q2. The initial phase of glycolysis is known as the energy investment phase. How many molecules of ATP are consumed in this initial phase?
Show answer & explanation
Correct answer: D — 4 ATP
The energy investment phase requires the input of 2 molecules of ATP to destabilize the glucose molecule for subsequent cleavage.
Q3. Where does the process of glycolysis primarily occur in a eukaryotic cell?
Show answer & explanation
Correct answer: B — Cytoplasm
Glycolysis is the metabolic pathway that breaks down glucose into pyruvate, and it occurs in the cytosol (cytoplasm) of the cell, not inside the mitochondria.
Q4. Which molecule is the immediate end product of glycolysis that can be further metabolized in anaerobic conditions?
Show answer & explanation
Correct answer: C — Pyruvate
Pyruvate is the end product of glycolysis. If oxygen is absent, pyruvate is converted to lactate (fermentation).
Q5. What is the fate of the three-carbon molecule (pyruvate) immediately following glycolysis, under aerobic conditions?
Show answer & explanation
Correct answer: C — Conversion to Acetyl CoA
Under aerobic conditions, pyruvate is transported into the mitochondria where it is converted into Acetyl CoA for the Citric Acid Cycle.
Q6. Which of the following molecules is the initial substrate for the glycolytic pathway in the cytoplasm of the cell?
Show answer & explanation
Correct answer: A — Glucose
Glycolysis is the metabolic pathway that breaks down glucose (a 6-carbon sugar) into two molecules of pyruvate. Glucose serves as the starting substrate for this pathway in the cytoplasm.
Q7. What is the primary fate of the three-carbon molecule pyruvate immediately following glycolysis?
Show answer & explanation
Correct answer: B — Reduced to Pyruvate
In the presence of oxygen, pyruvate is transported into the mitochondria to be further oxidized in the Citric Acid Cycle (via Acetyl-CoA). Under anaerobic conditions, it is converted to lactate.
Q8. Glycolysis is fundamentally an anaerobic process because it does not require oxygen for its completion. What is the primary purpose of glycolysis in terms of energy production?
Show answer & explanation
Correct answer: D — To produce large amounts of NADH
Although it is anaerobic, glycolysis is the initial step that generates a small but rapid supply of ATP and NADH, which are crucial for subsequent energy reactions.
Q9. Which of the following molecules serves as the initial substrate for the glycolytic pathway?
Show answer & explanation
Correct answer: A — Glucose
Glucose is the six-carbon sugar that is initially broken down via glycolysis to generate energy.
Q10. Where does the entire process of glycolysis take place in the cell?
Show answer & explanation
Correct answer: A — Cytoplasm
Glycolysis is a metabolic pathway that occurs in the cytoplasm of the cell, independent of oxygen availability.
Q11. The initial stage of glycolysis requires an investment of which type of energy molecules?
Show answer & explanation
Correct answer: C — ATP and Phosphate groups
The initial steps of glycolysis consume 2 molecules of ATP to phosphorylate the glucose molecule, thus investing energy to prepare for energy payoff.
Q12. Which molecule is the end product of glycolysis that is subsequently oxidized in the subsequent steps of cellular respiration?
Show answer & explanation
Correct answer: D — Pyruvate
Pyruvate is the three-carbon molecule that is the key intermediate produced at the end of glycolysis, which then proceeds to the Citric Acid Cycle (Krebs cycle).
Q13. What is the fate of the pyruvate molecule immediately after it is produced during glycolysis?
Show answer & explanation
Correct answer: B — It is converted into Lactate (in anaerobic conditions)
Under anaerobic conditions, pyruvate is converted into lactate. Under aerobic conditions, it is converted into Acetyl CoA to enter the next stage of respiration.
Q14. Glycolysis is an anaerobic process. What is the primary role of glycolysis?
Show answer & explanation
Correct answer: A — To produce a small amount of ATP quickly
Glycolysis is an anaerobic pathway that provides a rapid, albeit small, yield of ATP to the cell, which is essential even without oxygen.
Q15. Which molecule serves as the starting material (reactant) for the process of glycolysis?
Show answer & explanation
Correct answer: D — Glucose
Glycolysis begins with the breakdown of glucose, which is the primary six-carbon sugar used as the initial substrate.
Keep going — practice on Padhai Karlo
Padhai Karlo gives you unlimited NEET practice: chapter-wise questions, timed quizzes, and full mock tests with an All-India Rank — free to start.
Get the free Android app →