Question

When comparing replication and transcription, pick the best answer that describes this property:

the beginning of synthesis first requires a polymerase that uses rNTPs to make short oligomers/strands of 5-10 nucleotides

	A.	replication only
	B.	transcription only
	C.	neither
	D.	both

When comparing replication and transcription, pick the best answer that describes this property:

the process starts in a region of DNA that is rich in AT base pairs

	A.	replication only
	B.	transcription only
	C.	neither
	D.	both

Answer 1

1, A, replication only

In replication, inorder to initiate the addition of nucleotides, RNA primer is required. It is a short RNA strand synthesised by RNA primase. It must be synthesised before the replication of DNA starts. RNA primer is important for initiating DNA synthesis because DNA Polymerase cannot initiate addition of nucleotides without it.

In transcription, RNA Polymerase do not require a primer to add nucleotides

2, D, Both

In transription. the -10 region of the promoter called as TATA box is rich in AT nucleotides. RNA polymerase senses this initiation site site and starts transcription of DNA into mRNA.

In replication, AT rich region is initially unwound or separated by the DNA binding proteins. It is because that AT regions are double bonded and easily unwound when compared to GC sites