From the statements given below choose the correct option: A. The eukaryotic ribosomes are 80S and prokaryotic ribosomes are 70S. B. Each ribosome has two sub-units. C. The two sub-units of 80S ribosome are 60S and 40S while that of 70S are 50S and 30S. D. The two sub-units of 80S ribosome are 60S and 20S and that of 70S are 50S and 20S. E. The two sub-units of 80S are 60S and 30S and that of 70S are 50S and 30S.
Answer: (C) A, B, C are true. Answer: (C) A, B, C are true Solution: A is true (eukaryotic 80S, prokaryotic 70S), B is true (each ribosome has two subunits), and C is true (80S = 60S + 40S; 70S = 50S + 30S).
- A.A, B, E are true
- B.B, D, E are true
- C.A, B, C are true✓
- D.A, B, D are true
Correct Answer
(C) A, B, C are true
Solution & Explanation
Answer: (C) A, B, C are true Solution: A is true (eukaryotic 80S, prokaryotic 70S), B is true (each ribosome has two subunits), and C is true (80S = 60S + 40S; 70S = 50S + 30S). Statements D (60S+20S / 50S+20S) and E (60S+30S / 50S+30S) give wrong subunit values, so they are false. Hence A, B, C are correct, option (c). NCERT Reference: Ch 8, p.98, lines 33-37: "The eukaryotic ribosomes are 80S while the prokaryotic ribosomes are 70S. Each ribosome has two subunits... The two subunits of 80S ribosomes are 60S and 40S while that of 70S ribosomes are 50S and 30S."