Living beings maintain continuity of life by:
1. | Adaptation |
2. | DNA–replication and its transfer in the next generation |
3. | RNA synthesis |
4. | None of the above |
Which of the following is correct about H-bonding in nucleotide:
1. A–T G–C
2. A–G T–C
3. G–T A–C
4. A–A T–T
Chargaff's rule states that in an organism:
1. | The amount of adenine (A) is equal to that of thymine (T) and the amount of guanine (G) is equal to that of cytosine (C). |
2. | The amount of adenine (A) is equal to that of guanine (G) and the amount of thymine (T) is equal to that of cytosine (C). |
3. | The amount of adenine (A) is equal to that of cytosine (C) and the amount of thymine (T) is equal to that of guanine (G). |
4. | Amounts of all bases are equal. |
During translation initiation in prokaryotes, a GTP molecule is needed in:
1. | Formation of formyl-met-tRNA |
2. | Binding of 30S subunit of the ribosome with mRNA |
3. | Association of 30 S-mRNA with formyl met-tRNA |
4. | Association of 50 S subunit of the ribosome with the initiation complex |
In the genetic code dictionary, how many codons are used to code for all the 20 essential amino acids:
1. 20
2. 64
3. 61
4. 60
What does "lac" refer to in what we call the lac operon:
1. Lactose
2. Lactase
3. Lac insect
4. The number 1,00,000
Degeneration of a genetic code is attributed to the:
1. First member of a codon
2. Second member of a codon
3. Entire codon
4. Third member of a codon
During transcription, the DNA site at which RNA polymerase binds is called:
1. Promoter
2. Regulator
3. Receptor
4. Enhancer
What would happen if in a gene encoding a polypeptide of 50 amino acids, the 25th codon (UAU) is mutated to UAA?
1. | A polypeptide of 25 amino acids will be formed |
2. | Two polypeptides of 24 and 25 amino acids will be formed |
3. | A polypeptide of 49 amino acids will be formed |
4. | A polypeptide of 25 amino acids will be formed |
Which one of the following triplet codes, is correctly matched with its specificity for an amino acid in protein synthesis or as a 'start' or 'stop' codon:
1. UCG – Start
2. UUU – Stop
3. UGU – Leucine
4. UAC – Tyrosine