Question

Which of the following would be synthesized using 5′-CAGTTCGGA-3′ as a template?

a) 3'-GTCCTTCCT-5'
b) 3'-GTCUGCCA-5'
c) 3'-CAGUUCGGA-5'
d) 3'-CATTCAGTC-5'

Answer 1

The complementary sequence synthesized using 5'-CAGTTCGGA-3' as a template, following the rules of base pairing and synthesis direction, would be 3'-GTCCTTCCT-5', which is option A.

Step-by-step explanation:

The question asks for a sequence that would be synthesized using 5'-CAGTTCGGA-3' as a template. To determine the synthesized strand, we must identify the sequence that is complementary and antiparallel to the given template. DNA is always synthesized in the 5' to 3' direction, and the complementary base pairing is A with T (or U in RNA) and C with G.

Therefore, the correct answer is the sequence that pairs up with the template sequence accordingly, ensuring that adenine (A) pairs with thymine (T) and cytosine (C) pairs with guanine (G). The option that adheres to all the rules of base pairing and the direction of DNA synthesis is: 3'-GTCCTTCCT-5'.

This sequence is complementary and runs in the opposite direction (antiparallel) to the template sequence 5'-CAGTTCGGA-3'. Therefore, the correct response from the options provided is option A: 3'-GTCCTTCCT-5'.