BIOL 3301 EXAM QUESTIONS AND ANSWERS LATEST UPDATE (GRADED A+)

BIOL 3301 EXAM QUESTIONS AND ANSWERS
LATEST UPDATE (GRADED A+)
siRNA, small interfering RNA

Small RNAs that act in genome defense by preventing the spread of viruses and transposable elements.

Overview of Transcription

-Recognize transcription start site
-Unwind DNA
-Generate RNA strand (complementary to template strand)
-Elongation of new RNA is always 5' to 3'

RNA is

-transcribed from one of the 2 DNA strands.
-"copied" from the template strand and
"identical" to the non-template strand.

How does the RNA polymerase know where to start?

-It recognizes promoter sequences
-They are 5' or "upstream" of the gene
-The first transcribed base is the initiation site of transcription and is numbered +1

What is a promoter?

-Is a double-stranded DNA sequence that is the RNA polymerase binding site
-Bind other transcription proteins
-is located a short distance upstream of the coding sequence, within a few nucleotides of +1

What is at the -10 position?

Pribnow box, or -10 consensus sequence

Pribnow box, or -10 consensus sequence

5'-TATAAT-3'

What is at the -35 position?

6-bp region

The -35 consensus sequence

5'-TTGACA-3'

Coding strand

Identical to RNA sequence

Core Enzyme