Question

At a specific area of a chromosome, the sequence of nucleotides below is present where the chain opens to form a replication fork:
3' C C T A G G C T G C A A T C C 5'
An RNA primer is formed starting at the underlined T (T) of the template. Which of the following represents the primer sequence?

A) 5' G C C T A G G 3'
B) 3' G C C T A G G 5'
C) 5' A C G T T A G G 3'
D) 5' A C G U U A G G 3'
E) 5' G C C U A G G 3'

Answer 1

Answer: D

Explanation:

3' C C T A G G C (T) G C A A T C C 5'

The primer RNA will be 5' A C G U U A G G 3'

Polymerization of the new stand is taking place from 5' to 3' direction. This means the the template strand is read from 3' to 5' direction.

In DNA synthesis chargaff base pairing rule is always maintain. If ''A'' is present on the template strand ''T''enters in that place on the newly synthesized DNA .

RNA primase synthesizes this short primer. RNA primer contains RNA nucleotides this means If ''A'' is on the template strand, the RNA primer will be ''U''