AP BIOLOGY

Detailed explanation-1: -Specifically, RNA polymerase builds an RNA strand in the 5’ to 3’ direction, adding each new nucleotide to the 3’ end of the strand. RNA polymerase synthesizes an RNA strand complementary to a template DNA strand.

Detailed explanation-2: -Step 3: Termination Termination is the ending of transcription, and occurs when RNA polymerase crosses a stop (termination) sequence in the gene. The mRNA strand is complete, and it detaches from DNA.

Detailed explanation-3: -Any single strand of DNA/RNA will always have an unbound 5’ phosphate at one end and an unbound 3’ hydroxyl group at the opposite end. DNA is always read in the 5’ to 3’ direction, and hence you would start reading from the free phosphate and finish at the free hydroxyl group.

Detailed explanation-4: -Glossary:3’ (3-prime) A term that identifies one end of a single-stranded nucleic acid molecule. The 3’ end is that end of the molecule which terminates in a 3’ phosphate group. The 3’ direction is the direction toward the 3’ end.

Detailed explanation-5: -Note that while the RNA chain grows in a 5’ to 3’ direction the polymerase migrates along the sense strand in a 3’ to 5’ direction. Thus the 5’ to 3’ ribonucleotide sequence of the RNA transcript is identical to the 5’ to 3’ antisense DNA strand with uracil in place of thymidine.