Class 10 Science Chapter 5 Respiration Concept Clarity MCQs with Answers (CBSE 2026)

Practice these Concept Clarity MCQs from Class 10 Science Chapter 1 – Life Processes to strengthen your understanding of important NCERT concepts. These CBSE-based objective questions with answers are designed to improve conceptual understanding rather than rote learning. Solve these MCQs and test your knowledge of respiration, ATP, gaseous exchange, and other key topics to prepare effectively for school and board examinations.

Class 10 Science Chapter 1 – Life Processes Concept Clarity MCQs

Q1. During glycolysis, one molecule of glucose (6-carbon) is converted into:

(a) One 3-carbon pyruvate molecule
(b) Two 3-carbon pyruvate molecules 
(c) Two 2-carbon acetyl-CoA molecules
(d) One 4-carbon oxaloacetate molecule

Q2. Where does the breakdown of pyruvate in the presence of oxygen take place?

a) Cytoplasm (b) Nucleus (c) Mitochondria (d) ER 

Q3. What are the end products of the breakdown of one pyruvate molecule in the presence of oxygen?
a) 1 molecule of CO₂ (b) 3 molecules of CO₂ (c) H₂O (d) Both b and c

Q4. ATP supplies energy for which type of cellular reactions?

a) Endothermic (b) Exothermic (c) Oxidation (d) Both a and b

Q5. What is used to break the terminal phosphate in ATP?

a) Oxygen (b) Carbon dioxide (c) Water (d) None of these

Q6. Which statement is correct?

a) At night, oxygen release is the major event.

b) During the day, carbon dioxide produced in respiration is used in photosynthesis.

c) Plants do not respire during the day.

d) Carbon dioxide is released in large amounts during the day.

Q7. In fishes, oxygen enters the blood through the:

a) Mouth (b) Heart (c) Gills (d) Liver

Q8. Which statement is correct?

a) Cartilage rings help in gas exchange.

b) Cartilage rings absorb oxygen from air.

c) Cartilage rings prevent the air passage from collapsing.

d) Cartilage rings are present inside the lungs. 

Q9. Large animals require respiratory pigments because:

a) Their lungs cannot absorb oxygen.

b) Their blood contains less water.

c) Diffusion alone cannot supply oxygen efficiently to all body cells.

d) They produce less carbon dioxide.

Q10. Why do the lungs always contain a residual volume of air even after exhalation?

a) To prevent the alveoli from bursting.

b) To keep the lungs warm.

c) To provide sufficient time for oxygen to be absorbed and carbon dioxide to be released.

d) To increase the amount of carbon dioxide in the blood.

🧠 TopperGuru1 Concept Check

Before checking the answer key, ask yourself these two questions for every MCQ:

✅ Why is the correct option right?

✅ Why are the other three options wrong?

If you can explain both, your concept is truly clear. If not, revise the related NCERT concept and try again.

Remember: Real learning happens when you understand the reason, not when you memorize the answer.

Answer Key:-

Q1 – (b) | Q2 – (c) | Q3 – (d) | Q4 – (a) | Q5 – (c) | Q6 – (b) | Q7 – (c) | Q8 – (c) | Q9 – (c) | Q10 – (c)

These Class 10 Science Chapter 1 – Life Processes Concept Clarity MCQs are designed to help students develop a strong understanding of NCERT concepts instead of relying on memorization. Regular practice of these CBSE and NCERT-based MCQs will improve conceptual clarity, logical thinking, and exam performance. For more chapter-wise MCQs, Assertion & Reason Questions, Case-Based Questions, PYQs, and NCERT Solutions, keep visiting TopperGuru1 and make your board exam preparation more effective.

Also check: Assertion & Reason Questions, Case-Based Questions, Important MCQs, and NCERT Extra Questions from Class 10 Science Chapter 1 – Life Processes on TopperGuru1.