MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 16 Mcqs, each offering curated multiple-choice questions to sharpen your Biochemistry knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The codons which do not specify an amino acid are called |
| A. | initiation code |
| B. | termination code |
| C. | propagation code |
| D. | none of these |
| Answer» C. propagation code | |
| 2. |
The genetic code is degenerated. Which of the following codons represents the principle of degeneracy? |
| A. | UAA and UAC |
| B. | AUG and AUA |
| C. | CAU and CAC |
| D. | UUA and UUC |
| Answer» D. UUA and UUC | |
| 3. |
Translation begins |
| A. | at the replication fork |
| B. | on the lagging strand |
| C. | at the start codon |
| D. | in nucleus |
| Answer» D. in nucleus | |
| 4. |
The sequence of one strand of DNA is: 5' ATTGCCA 3', what is the sequence of the other strand? |
| A. | 5' TAACGGT 3' |
| B. | 5' TGGCAAT 3' |
| C. | 5' ATTGCCA 3' |
| D. | 5' UAAGCCU3' |
| Answer» C. 5' ATTGCCA 3' | |
| 5. |
In prokaryotes, AUG encodes |
| A. | methionine |
| B. | N-formyl methionine |
| C. | a stop codon |
| D. | alanine |
| Answer» C. a stop codon | |
| 6. |
How many amino acids will be encoded by 5' GAU GGU UGA UGU 3' sequence? |
| A. | One |
| B. | Two |
| C. | Three |
| D. | Four |
| Answer» C. Three | |
| 7. |
In protein synthesis in prokaryotes |
| A. | the initiating amino acid is N- formyl methionine |
| B. | the initiating amino acid is methionine |
| C. | the initiating amino acid is phenyl alanine |
| D. | none of the above |
| Answer» B. the initiating amino acid is methionine | |
| 8. |
AUG codes for methionine act as a |
| A. | initiation code |
| B. | elongation code |
| C. | termination code |
| D. | propagation code |
| Answer» B. elongation code | |
| 9. |
Crick demonstrated that the genetic code involved three bases and suggested that the code was degenerated. What experimental technique Crick conducted to suggest genetic code degeneration? |
| A. | Gel electrophoresis |
| B. | Density gradient centrifugation |
| C. | Frameshift mutagenesis |
| D. | Restriction digests of the rII gene |
| Answer» D. Restriction digests of the rII gene | |
| 10. |
In some organelles in eukaryotes, the genetic code for some codons |
| A. | differs from that used in prokaryotes |
| B. | are same |
| C. | are partially same |
| D. | none of the above |
| Answer» B. are same | |
| 11. |
Which of the following techniques was carried out by Nirenberg and Matthaei in 1961 to determine the first codon? |
| A. | In vitro synthesis of a polypeptide using UUUUU |
| B. | Labeled peptide binding to a ribosome |
| C. | Mixed co-polymer mRNA synthesis |
| D. | none of the above |
| Answer» B. Labeled peptide binding to a ribosome | |
| 12. |
Bacterial protein called catabolic activator protein (CAP) is an example of |
| A. | negative control of gene expression |
| B. | positive control of gene expression |
| C. | second type of positive control of gene expression |
| D. | none of the above |
| Answer» D. none of the above | |
| 13. |
How many different codons are possible? |
| A. | 3 |
| B. | 20 |
| C. | 64 |
| D. | An infinite number |
| Answer» D. An infinite number | |
| 14. |
The genetic code is |
| A. | universal |
| B. | universal except for rare exceptions in mitochondria and some protozoa |
| C. | species-specific |
| D. | kingdom-specific |
| Answer» C. species-specific | |
| 15. |
Which of the following has been used as an evidence that primitive life forms lacked both DNA and enzymes? |
| A. | RNA can both code genetic information and act as a catalyst |
| B. | DNA and enzymes are only present in the most advanced cells |
| C. | Advanced cells lack RNA |
| D. | All of the above |
| Answer» B. DNA and enzymes are only present in the most advanced cells | |
| 16. |
Codon that specify the amino acids often differs in the |
| A. | first base |
| B. | second base |
| C. | third base |
| D. | none of these |
| Answer» D. none of these | |