MCQs on Electron Transport System

The Electron Transport System (ETS) or Electron transport chain is present in the inner mitochondrial membrane. It contains several electron transporters in a series, which facilitate the movement of electrons from one carrier to another in redox reactions. The NADH and FADH2 produced during the citric acid cycle get oxidised. It results in the formation of a proton gradient across the membrane and which stimulates the formation of ATP by oxidative phosphorylation during cellular respiration.

1. Which of the following is the correct sequence of electron acceptors in ETS for production of ATP?

(a) Cyt b, c, a, a3

(b) Cyt a, a, b, c

(c) Cyt c, b, a, a3

(d) Cyt b, c, a3, a

Answer: (a)

2. Which of the following terminal cytochromes is responsible for donating electrons to oxygen?

(a) Cyt a3

(b) Cyt b

(c) Cyt c

(d) Cyt a1

Answer: (a)

3. Electron transport system (ETS) is present in which of the following parts of mitochondria?

(a) Inner membrane

(b) Outer membrane

(c) Matrix

(d) Stroma

Answer: (a)

4. Which of the following is the first complex (Complex I) of ETS?

(a) NADH dehydrogenase

(b) Cytochrome aa3

(c) Cytochrome bc1

(d) ATP synthase

Answer: (a)

5. Which of the following is the Complex III of ETS?

(a) NADH dehydrogenase

(b) Cytochrome aa3

(c) Cytochrome bc1

(d) ATP synthase

Answer: (c)

6. Ubiquinone transfers its electrons to

(a) Complex I

(b) Complex II

(c) matrix

(d) Cyt c

Answer: (d)

7. In which part of the cell, oxidative phosphorylation takes place?

(a) Inner mitochondrial membrane

(b) Outer mitochondrial membrane

(c) Grana of chloroplast

(d) Stroma of chloroplast

Answer: (a)

8. Cytochromes are present in

(a) lysosomes

(b) mitochondrial matrix

(c) cristae of mitochondria

(d) outer membrane of mitochondria

Answer: (c)

9. ATP synthesis by ATP synthase is driven by the movement of

(a) protons

(b) NADH

(c) electrons

(d) All of the above

Answer: (a)

10. Oxidative phosphorylation results in the formation of

(a) Oxygen

(b) ADP

(c) ATP + H2O

(d) NADH

Answer: (c)

11. Which of the following complexes of ETS does not account for the pumping out of protons from the mitochondrial matrix?

(a) Complex I

(b) Complex III

(c) Complex II

(d) Complex IV

Answer: (c)

12. Which of the following is the Complex IV of ETS?

(a) NADH dehydrogenase

(b) Cytochrome c oxidase

(c) Cytochrome bc1

(d) Succinate dehydrogenase

Answer: (b)

13. Which of the following is the Complex II of ETS?

(a) NADH dehydrogenase

(b) Succinate dehydrogenase

(c) Cytochrome bc1

(d) ATP synthase

Answer: (b)

14. Which of the following products of glucose oxidation are necessary for oxidative phosphorylation?

(a) Pyruvate

(b) NADH and FADH2

(c) Acetyl CoA

(d) NADPH and ATP

Answer: (b)

15. Which of the following is true for cytochrome c oxidase complex?

(a) It donates electrons to O2

(b) It accepts electrons from Cyt c

(c) It pumps two protons out of the mitochondrial matrix

(d) All of the above

Answer: (d)

These were some MCQs on the Electron Transport System. Learn MCQs on related topics for NEET, at BYJU’S.

Leave a Comment

Your email address will not be published. Required fields are marked *