Lac operon is an example of

(1) both positive and negative regulation

(2)only negative regulation

(3)only positive regulation

(4)sometimes positive sometimes negative

Lac operon inhibition by repressor is an example of

(1) negative regulation

(2)positive regulation

(3)neither positive nor negative

(4) both positive and negative regulation

Regulation of lac operon can be visualised as regulation of enzyme synthesis by its

(1) substrate

(2)lactose

(3)carbohydrates

(4)All of these

Lac operon will be switched on when

(1) lactose is less in the medium

(2)glucose is enough in the medium

(3)lactose is less than glucose

(4)lactose is more than glucose

Repressor mRNA will be formed in

(1) absence of inducer

(2) presence of inducer

(3) both 1 and 2

(4) presence of lac mRNA

The order and sequence of amino acids are defined by

(1) Nucleotides sequences in DNA

(2) Nucleotides sequences in mRNA

(3) Nucleotides sequences in template strand of DNA

(4) Nucleotides sequences in non- template strand of DNA

Formation of peptide bond is

(1) active process

(2) passive process

(3) both active and passive process

(4) neither active nor passive process

Which of the following is incorrect for protein synthesis

(1) Ribosomes are the cellular for protein synthesis

(2) 23s rRNA act as catalyst for peptide bond formation in all organisms

(3) UTR are required for efficient translation process

(4) The ribosome proceeds to the elongation phase of protein synthesis

In bacteria catalytic RNA is found in

(1) 60S subunit of ribosome

(2) 40S subunit of ribosome

(3) 30S subunit of ribosome

(4) 50S subunit of ribosome

Untranslated regions (UTRs) are present

(1) before and after the stop codon

(2) after the start codon and before the stop codon

(3) before and after the start codon

(4) before the start codon and after the stop codon