Final answer:
To find the complementary DNA sequence to the given strand 5'-CGATATTGAGCTAAGCTT-3', we apply the base pairing rules and write the sequence in reverse order, which results in 3'-GCTATAACTCGATTCGAA-5'.
Step-by-step explanation:
The student has inquired about finding the complementary DNA sequence to a given strand. In DNA, complementary bases pair as follows: Adenine (A) pairs with Thymine (T), and Guanine (G) pairs with Cytosine (C). To write the complementary sequence for the provided DNA strand from 3' to 5', we must identify the base that pairs with each given nucleotide in the sequence, while keeping in mind that the complementary strand will be oriented in the opposite direction.
The given sequence is 5'-CGATATTGAGCTAAGCTT-3'. By applying the base pairing rules, we determine that the complementary sequence will be 3'-GCTATAACTCGATTCGAA-5', noting that we've reversed the order since we are writing from the 3' to 5' direction. It's important to remember that the strands of DNA are anti-parallel, meaning they run in opposite directions relative to each other.