DNA

Question 1

What is the characteristic DNA sequence (2 important ones) of the promotor region?

Answer 1

2 sequences:

• 25 TATA box (Hogness box)
• 75 CAAT box

Question 2

What does the mutation in the DNA sequence cause???

Answer 2

Mutations in a promotor region cause less promotion… thus less transcription of these genes, thus decreases the amount of gene that is transcribed.

Question 3

What structural motifs allow for proteins to bind to DNA?

Answer 3

• Helix-loop-helix
• Helix-turn-helix
• Zinc finger motif
• Leucine zipper protein

Question 4

What are the different RNA polymerases in Eukaryotes? What about prokaryotes?

Answer 4

RNA Polymerase I - rRNA
RNA polymerase II- mRNA
RNA polymerase III- tRNA

Prokaryotes: 1 type of RNA polymerase, makes 3 types of RNA

Question 5

What enzyme is responsible for tRNA charging?

Answer 5

Aminoacyl tRNA synthetase

Question 6

What enzyme catalyzes peptide bond formation?

Answer 6

Peptidyl transferase

Question 7

What enzyme is deficient in Lech-Nyhan syndrome? What is the TX?

Answer 7

Hypoxanthine-guanine phosphoribosyltransferase (HGPRT)

Tx- Allopurinol