Molecular Basis of Inheritance

What would happen if in a gene encoding a polypeptide of 50 amino acids, 25th codon (UAU) is mutated to UAA?

1. A polypeptide of 49 amino acids will be formed
2. A polypeptide of 25 amino acids will be formed
3. Two polypeptides of 24 and 25 amino acids will be formed
4. A polypeptide of 24 amino acids will be formed

What does "lac" refer to in what we call the lac operon?

1. The number 1,00,000
2. Lac insect
3. Lactase
4. Lactose

During translation initiation in prokaryotes, a GTP molecule is needed in:

1. Association of 30S-mRNA with formyl-met-tRNA
2. Formation of formyl-met-tRNA
3. Association of 50S subunit of ribosome with initiation complex
4. Binding of 30S subunit of ribosome with mRNA

Which one of the following triplet codes, is correctly matched with its specificity for an amino acid in protein synthesis or as 'start' or 'stop' codon?

1. UUU – Stop
2. UAC – Tyrosine
3. UGU – Leucine
4. UCG – Start

During transcription, the DNA site at which RNA polymerase binds is called:

1. Receptor
2. Regulator
3. Enhancer
4. Promoter

Degeneracy of a genetic code is attributed to the:

1. Second member of a codon
2. Third member of a codon
3. First member of a codon
4. Entire codon

In the genetic code dictionary, how many codons are used to code for all the 20 amino acids:

1. 64
2. 20
3. 60
4. 61

In a DNA percentage of thymine is 20% then what is the percentage of guanine : -

1. 40%
2. 20%
3. 30%
4. 60%

Transformation experiment was first performed on which bacterium : -

1. Diplococcus pneumoniae
2. Pasteurella pestis
3. E. coli
4. Salmonella

Jacob and Monod studied lactose metabolism in E. coli and proposed operon concept. Operon concept is applicable for :

1. All prokaryotes and all eukaryotes
2. All prokaryotes and some protozoans
3. All prokaryotes
4. All prokaryotes and some eukaryotes