Question

We know that the nitrogen bases of DNA, T-A and C-G, act as a template in building new DNA molecules during replication. But before replication can begin, an enzyme called ________ must _____________, starting at the replication origin. Responses A helicase; split open the DNAhelicase; split open the DNA B DNA primase; split open the DNADNA primase; split open the DNA C DNA polymerase; match nitrogen basesDNA polymerase; match nitrogen bases D ligase; insert the correct nitrogen basesligase; insert the correct nitrogen bases

Answer 1

In summary, the correct answer is A) helicase; split open the DNA. Helicase is responsible for separating the DNA strands, allowing replication to proceed.

Step-by-step explanation:

Before replication can begin, an enzyme called helicase must split open the DNA, starting at the replication origin.

Here's a step-by-step explanation:

1. Replication is the process of making an identical copy of DNA. It is necessary for cell division and the transmission of genetic information.

2. The two strands of DNA in the double helix structure need to be separated or "unzipped" before replication can occur. This is where the enzyme helicase comes in.

3. Helicase is responsible for breaking the hydrogen bonds between the nitrogen bases of the DNA molecule. These nitrogen bases are adenine (A), thymine (T), cytosine (C), and guanine (G).

4. Once helicase splits open the DNA, it creates two separate strands. Each strand now serves as a template for the synthesis of a new DNA molecule.

5. Now that the DNA strands are separated, the next step is to match the correct nitrogen bases to each template strand. Adenine (A) pairs with thymine (T), and cytosine (C) pairs with guanine (G). This is where DNA polymerase comes in.

6. DNA polymerase is an enzyme that matches the appropriate nitrogen bases to each template strand. It ensures that the new DNA molecules are complementary to the original DNA strands.

So, in summary, the correct answer is A) helicase; split open the DNA. Helicase is responsible for separating the DNA strands, allowing replication to proceed.