Multiple Choice Questions on Ribosomes

1. All the following sites has ribosomes except

a) nucleus
b) mitochondrion
c) chloroplast
d) cytoplasm

2. Ribosomes are present in
a) Eukaryotes only
b) Eukaryotes and prokaryotes
c) Prokaryotes only
d) Eukaryotes, prokaryotes and viruses

3. In 70S ribosomes, ‘S’ stands for
a) SI unit
b) Solubility factor
c) Svedberg unit
d) all of these

4. 80 S ribosomes occur in
a) Eukaryotic cells of animals
b) Eukaryotic cells of animals and plants
c) Both Eukaryotic cells and prokaryotic cells
d) all of these

5. The subunits of 80S ribosome include

a) 40S and 50S
b) 30S and 50S
c) 40S and 60S
d) 20S and 60S

6. Which of the following ions are required for binding of ribosomal subunits
a) Na+
b) Mg++
c) Mn++
d) Fe++

7. 70S ribosome occur in
a) viruses
b) prokaryotes
c) prokaryotes and eukaryotic plant cells
d) All of these

8. The larger and smaller subunit of 70S ribosome is


a) 50S and 30S
b) 30S and 40S
c) 40S and 20S
d) 20S and 50S

9. Ribosomes are made up of
a) RNA only
b) RNA and proteins
c) RNA, DNA and proteins
d) Nucleic acids, proteins and lipids

10. Polysomes are
a) multiple units of ribosomes
b) attachment of many ribosomes to a common mRNA
c) attachment of many mRNA to a common ribosomes
d) lysosomal aggregations

11. The rRNA subunits of 70S ribosome are



a) 23S in larger 50S ribosomal subunit and 16S and 5S rRNA in smaller 30S ribosomal subunit
b) 23S and 5S in larger 50S ribosomal subunit and 16S rRNA and 5S in smaller 30S ribosomal subunit
c) 28S and 5S in larger 50S ribosomal subunit and 16S rRNA in smaller 30S ribosomal subunit
d)23S and 5S in larger 50S ribosomal subunit and 16S rRNA in smaller 30S ribosomal subunit

12. Chloramphenicol inhibits
a) bacterial ribosomes
b) plant ribosomes
c) both a and b
d) animal ribosomes

13. Which of the following organelle lack ribosomes
a) mitochondrion
b) nucleus
c) chloroplast
d) RER

14. Protein synthesis by eukaryotic ribosomes is inhibited by
a) Chloramphenicol
b) cycloheximide
c) Penicillin
d) Cinchonine 

15. Which of the following statements are true
a) Ribosomes are self-replicating organelles
b) Ribosomes are double membrane bound organelles
c) Ribosomal components are coded by DNA
d) Ribosomes are deoxyribonucleoproteins

16. Ribosomes are attached to endoplasmic reticulum so as to form rough endoplasmic reticulum mediated by

a) Ribophorin I 

b) Ribophorin II

c) Both (A) and (B) 

d) Magnesium linked protein

17. Which sub unit of ribosome is attached to ER?

a) 50S 

b) 60S 

c) 30S 

d) 40S

18. The RNAs present in 80S Eukaryotes chromosomes

a) 23S rRNA, 5S rRNA and 16S rRNA

b) 28S rRNA, 5S rRNA, 5.8S rRNA and 18S rRNA

c) 28S rRNA, 5S rRNA and 16S rRNA

d) 23S rRNA, 5S rRNA and 18S rRNA

Learn more:

• MCQ on Cell and Cell Organelles
• MCQ on Nucleus
• MCQ on Plasma membrane
• MCQ on Endoplasmic Reticulum
• MCQ on Cell wall

Answers:
1. a) nucleus
2. b) Eukaryotes and prokaryotes
3. c) Svedberg unit
4. b) Eukaryotic cells of animals and plants
5. c) 40S and 60S
6. b) Mg++
7. b) prokaryotes
8. a) 50S and 30S
9. b) RNA and proteins
10. b) attachment of many ribosomes to a common mRNA
11. d) 23S and 5S in larger 50S ribosomal subunit and 16S rRNA in smaller 30S ribosomal subunit
12. a) bacterial ribosomes
13. b) nucleus
14. b) cycloheximide
15. c) Ribosomal components are coded by DNA

16. c) Both (A) and (B)

17. b) 60S 

18. b) 28S rRNA, 5S rRNA, 5.8S rRNA and 18S rRNA