A eukaryotic gene contains two kinds of base sequences. Which of these plays an important role in protein synthesis?

• Introns

• Exons

• Both 'a' and 'b'

• None of the above

The number of hydrogen bonds between adenine and thymine in a DNA molecule is :

• two

• three

• four

• eight

In DNA, which is absent ?

• Adenine

• Guanine

• Uracil

• Cytosine

Enzyme required for transcription is

• RNAse

• Endonuclease

• RNA polymerase

• DNA polymerase

Which of the following constitute about 10-20% of total circular RNA?

• m-RNA

• r -RNA

• t-RNA

• hn -RNA

Mutation is more common when it is present in:

• dominant condition

• recessive condition

• constant in population

• none of the above

The process of multiplication of DNA from DNA is known as

• replication

• transversion

• transcription

• translation

Which is called soluble RNA ?

• rRNA

• tRNA

• mRNA

• hnRNA

In DNA, which is absent :

• Adenine

• Thymine

• Guanine

• Uracil

Sequence of DNA (Non- coding) is known as:

• exon

• intron

• cistron

• none