The base sequence of the strand of DNA used as the template for transcription has the base sequence GATCTAC. What is the base sequence of RNA product?
**Core Concept**
The process of transcription involves converting a DNA template strand into a complementary RNA molecule, where uracil (U) replaces thymine (T) and adenine (A) remains unchanged, while guanine (G) remains unchanged and cytosine (C) remains unchanged.
**Why the Correct Answer is Right**
During transcription, RNA polymerase reads the DNA template strand and matches the incoming nucleotides to the base pairing rules: A-T, G-C, and A-U. In this case, the DNA template strand has the sequence GATCTAC. The RNA product will have the sequence AUGCAUGU, where U replaces T.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not replace T with U, violating the base pairing rules of transcription.
**Option B:** This option is incorrect because it replaces C with T, which is not a correct base pairing during transcription.
**Option C:** This option is incorrect because it introduces an incorrect base, which is not a product of the given DNA template strand.
**Clinical Pearl / High-Yield Fact**
Remember that transcription involves the replacement of T with U in the RNA product, a fundamental principle of molecular biology.
**Correct Answer:** C. AUGCAUGU