DNA replication and transcription similarities
Select the statement(s) that apply to both DNA replication and RNA transcription.
A) Separation of the DNA strands (“unzipping”).
B) A requirement for a primer.
C) Directionality of synthesis.
D) Base-pairing of complementary nucleotides.
E) Energy to drive the process is provided by triphosphate nucleotides
Answer :
All statements are common to both DNA replication and transcription except option: requirement for a primer.
Explanation:
A) Unzipping is essential for replication as unwinding of DNA strands exposes and thus bases can be read. In transcription both strands of DNA are separated to access the bases.
B) In transcription, RNA polymerase do not require primer as it is RNA. It requires promoter.
C) DNA polymerase synthesized from 5′ to 3′ direction and RNA polymerase synthesizes new RNA strand in the 5’ to 3’ direction
D) In replication, base pairing in DNA is always complementary base pairing in which adenine binds to thymine (A−T) by two bonds and guanine binds to cytosine (G−C) by three hydrogen bonds. Therefore, G−C bonding is stronger than A-T base pairing.
In transcription, DNA strand is copied into RNA. It also follows complementary base pairing but thymine is replaced with uracil. Therefore, Adenine pairs with Uracil in RNA and in Adenine pairs with Thymine in DNA.
E) ATP (Adenosine Triphosphate) is used as energy sources for various metabolic processes.
The DNA governs the construction of proteins, particularly the genetic material called genes. DNA is transcribed into messenger RNA (mRNA) and then translated into either non-coding RNA or into a protein, which is then carried out by the ribosome.
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