AP BIOLOGY

Detailed explanation-1: -The enzyme that converts DNA into mRNA is called RNA polymerase, which attaches to the DNA double helix as shown here. Once attached, RNA polymerase can unwind the helix and begin copying one of the DNA strands to form an mRNA transcript of the gene.

Detailed explanation-2: -Transcription always occurs in the 5’-3’ direction because it must be antiparallel to the complementary strand it is base paired with. So that means it will start at the 3’ end of its complementary strand and proceed in the 5’-3’ direction as it copies the gene on DNA into mRNA.

Detailed explanation-3: -Each end of DNA molecule has a number. One end is referred to as 5’ (five prime) and the other end is referred to as 3’ (three prime). The 5’ and 3’ designations refer to the number of carbon atom in a deoxyribose sugar molecule to which a phosphate group bonds.

Detailed explanation-4: -Therefore the anticodon for the tRNA for the mRNA codon 5’ GCA 3’ will be 3’ CGU 5’.