If a DNA strand has a base sequence TCA, its complementary strand must be?
Answer Details
The complementary strand of a DNA strand with base sequence TCA is AGT.
In DNA, each nucleotide base pairs with a specific partner: adenine (A) with thymine (T) and guanine (G) with cytosine (C). The base pairing rules dictate that the complementary strand of a DNA strand with base sequence TCA would have a base sequence of AGT, because adenine (A) pairs with thymine (T) and guanine (G) pairs with cytosine (C).
Therefore, the correct answer is AGT.