Molecular Basis of Inheritance

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

In E. coli, during lactose metabolism repressor binds to : -

1. Promoter gene
2. Operator gene
3. Structural gene
4. Regulator gene

Out of 64 codons, 61 codons code for 20 types of amino acids; it is called : -

1. Wobbling of codon
2. Universality of codons
3. Overlapping of gene
4. Degeneracy of genetic code

Which of the following reunites the exon segments after RNA splicing ?

1. RNA polymerase
2. RNA proteases
3. RNA primase
4. RNA ligase

Exon parts of mRNA have code for : -

1. Lipid
2. Protein
3. Phospholipid
4. Carbohydrate

m-RNA is synthesised on DNA template in which direction : -

1. Any
2. Both (3) and (4)
3. 5' → 3'
4. 3' → 5'

In Negative operon : -

1. cAMP has negative effect on lac operon
2. Co-repressor binds with inducer
3. Co-repressor binds with repressor
4. Co-repressor does not bind with repressor

Gene and cistron words are sometimes used synonymously because : -

1. One gene contains one cistron
2. One cistron contains many genes
3. One gene contains no cistron
4. One gene contains many cistrons

Types of RNA polymerase required in nucleus for RNA synthesis : -

1. 2
2. 3
3. 1
4. 4

A mutant strain of T4 bacteriophage, R-II, fails to lyse E. coli, but when two strains R-IIX and R-IIY are mixed, they lyse E. coli. What may be the possible reason?

1. Both strains have different cistrons
2. Both strains have similar cistrons
3. It is not mutated
4. Bacteriophage transforms into wild type