Question

what would be the complementary dna bases for this strand, starting from the top and going done?
□ gtcaat
□ att gac
□ taactg
□ uaacug

Explanation:

First, we need to know the base - pairing rules in DNA: Adenine (A) pairs with Thymine (T), and Guanine (G) pairs with Cytosine (C). But there seems to be a typo in the original strand (maybe it's "ATTGAC" as one of the options is related, or perhaps the original strand is "ATTGAC" and we need to find its complement). Wait, maybe the original DNA strand is "ATTGAC". Let's assume the original DNA strand is "ATTGAC".

Step 1: Pair A with T, T with A, G with C, C with G

For the first base 'A', its complement is 'T'.
For the second base 'T', its complement is 'A'.
For the third base 'T', its complement is 'A'.
For the fourth base 'G', its complement is 'C'.
For the fifth base 'A', its complement is 'T'.
For the sixth base 'C', its complement is 'G'.
Wait, maybe the original strand is "ATTGAC", then the complementary strand should be "TAACTG". Let's check the options. One of the options is "TAACTG". Let's verify the base - pairing again.
If the original DNA strand is, say, "ATTGAC":

• A pairs with T
• T pairs with A
• T pairs with A
• G pairs with C
• A pairs with T
• C pairs with G

So the complementary strand is T A A C T G, which is "TAACTG".

Answer:

TAACTG (the option with "TAACTG")