Question

what happens at the beginning of dna replication?
a. the code in the sequence of bases is transferred to an mrna molecule.
b. the two strands of dna are separated to form a y - shaped replication fork.
c. a group of enzymes attaches to the molecule and starts to build a new double helix.
d. rna primers are removed and replaced with dna nucleotides.

Explanation:

• Option A: Transferring code to mRNA is transcription, not DNA replication.
• Option B: At the start of DNA replication, helicase unwinds the DNA double helix, separating the two strands to form a Y - shaped replication fork.
• Option C: Enzymes building a new double helix occurs after the strands are separated.
• Option D: Removing RNA primers is a later step in DNA replication.

Answer:

B. The two strands of DNA are separated to form a Y - shaped replication fork.