Question

the base sequence of a segment of dna is shown. dna strand 1: 3 g c g t a c c 5 dna strand 2: 5 ? ? ? ? ? 3 which base sequence completes dna strand 2? a t a c c g t t a t g g c a g c c g t a c c c g c a t g

Explanation:

Step1: Identify base - pairing rules

In DNA, adenine (A) pairs with thymine (T), and cytosine (C) pairs with guanine (G).

Step2: Determine the complementary strand

DNA Strand 1 is \(3'\) - GCGGTAC - \(5'\).
For each base in Strand 1:

• G (in Strand 1) pairs with C.
• C pairs with G.
• G pairs with C.
• G pairs with C.
• T pairs with A.
• A pairs with T.
• C pairs with G.

And since DNA Strand 1 is \(3'\) to \(5'\), the complementary Strand 2 should be \(5'\) to \(3'\).
So the complementary strand is \(5'\) - CCGCATG - \(3'\).

Answer:

A. CCGCATG