RNA is not found in

• chromosome

• plasmalemma

• nucleolus

• ribosome

Sequence of DNA (non-coding) is known as

• exon

• intron

• cistron 

• none of these

Which one of the following makes use of RNA as a template to synthesize DNA?

• Reverse transcriptase

• DNA dependant RNA polymerase

• DNA polymerase

• RNA polymerase

During transcription holoenzyme RNA polymerase binds to a DNA sequence and the DNA assumes a saddle like structure at that point. What is that sequence called?

• CAAT box

• GGTT box

• AAAT box

• TATA box

Which one of the following hydrolysis internal phosphodiester bonds in a polynucleotide chain?

• Lipase

• Exonuclease

• Endonuclease

• Protease

E. coli cells with a mutated Z gene of the lac operon cannot grow in medium containing only lactose as the source of energy because

• in the presence of glucose, E. coli cells do not utilize lactose

• they cannot transport lactose from the medium into the cell

• the lac operon is constitutevely active in these cells

• they cannot synthesize functional $\mathrm{\beta }$- galactosidase

What's the difference between RNA and DNA?

• Base

• Sugar

• Sugar and base

• Phosphate

138.

In split genes the coding sequences are called

• introns

• exons

• cistrons

• operons

DNA replication generally proceeds in a 

• 5 $\to$3 direction

• 3 $\to$5 direction

• 3 $\to$3 direction

• 5 $\to$5 direction

DNA polymerase enzyme is required for synthesis of

• DNA from RNA

• RNA from DNA

• DNA from DNA

• RNA from RNA