Lecture 13.5 - 15 (Translation, Transcription,Regulation, DNA Replication)

Question 1

Where does the Ribosomes recognize and bind to on the mRNA template during Translation?

Answer 1

Shine-Dalgarno sequence

Question 2

IF2 delivers all activated tRNAs to Ribosome during translation
T/F

Answer 2

False. IF2 only delivers the 1st activated tRNA to Ribosome.

Question 3

Where does Translation start on the mRNA template?

Answer 3

6-9 base pairs downstream of the Shine-Dalgarno sequence

Question 4

How many stop codons are there for Translation?
A. 6
B. 3
C. 9
D. 1

Answer 4

B.

Question 5

Which of these antibiotics does NOT inhibit Translation
A. Amoxicillin
B. Tetracycline
C. Erythromycin
D. Chloramphenicol

Answer 5

A.

Question 6

How does the cell compensate for degeneracy in the genetic code?

Answer 6

Two ways:
1. By loose specificity in the 3rd base “wobble” position
2. Makes a 2nd tRNA for the same amino acid to recognize a particular codon

Question 7

What are Chaperones? And what can they do?

Answer 7

They are proteins that modify the folding of other proteins.
They can:
1. Accelerate proper folding
2. Inhibit Folding (Secretion)
3. Permit Refolding after a protein has ben denatured.

Question 8

Sigma factors are essential for what?
A. DNA polymerase binding
B. Ribosomal binding
C. RNA polymerase binding
D. Repressor binding

Answer 8

C.

Question 9

Where do sigma factors bind?
A. The -35 and -10 elements
B. On the operator
C. At the start codon
D. Upstream of the -35 element

Answer 9

A.

Question 10

How many Promoters are on 1 operon with 5 genes?

Answer 10

1 Promoter

Question 11

In the Lux operon (quorum sensing), LuxR acts as a what?
A. Inhibitor
B. Repressor
C. Autoinductor
D. Activator

Answer 11

D.

Question 12

In the Lac operon, if the operator site is mutated (loss of function), then what would occur?
A. The Lac operon will be turned on when glucose is not present.
B. The Lac operon will never be expressed.
C. The Lac operon will always be expressed.
D. The Lac operon will only be expressed when glucose is present.

Answer 12

B.

Question 13

In the Lac Operon what is the Repressor?

Answer 13

LacI

Question 14

In the Lac Operon what is the Autoinducer?

Answer 14

Lactose

Question 15

For a repressor, you would expect it to block what?
A. The RUT sites on a gene sequence
B. The stop codon
C. The mRNA Shine–Dalgarno sequence
D. The promoter region of the DNA.

Answer 15

D.

Question 16

In a two-component system the HK is phosphorylated on a specific 1. _______________
residue with a phosphate taken from ATP, while the RR is phosphorylated at a specific
2. __________________
residue with a phosphate from the HK.

Answer 16

1. Histidine
2. Aspartate

Question 17

Riboswitches and sRNAs typically will stop what process?
A. Replication
B. Translation
C. Transcription
D. Protein Folding

Answer 17

B.

Question 18

There is only one type of sigma factor in a cell, however, that single type depends on the bacterial species.
T/F

Answer 18

False

Question 19

What process are each of these proteins important for?

DnaA 1.__________

DNA polymerase III 2. _____

Tus Termination 3. ______

Topoisomerase IV 4. ______
Drop down Box:
A. Termination
B. Elongation
C. Decatenation
D. Initiation

Answer 19

1. D. Initiation
2. B. Elongation
3. A. Termination
4. C. Decatenation

Question 20

mRNA is polymerized in which direction?

Answer 20

5’ to 3’

Question 21

DNA template strand is read in which direction?

Answer 21

3’ to 5’

Question 22

What are the two methods to Transcription Termination?

Answer 22

1. Rho- Independent Termination
2. Rho-Dependent Termination

Question 23

Glucose can not be present while the Lac Operon is Activated (Gene expression is ON)
T/F

Answer 23

True

Question 24

What do Riboswitches do and where are they located?

Answer 24

They fold to regulate transcription, they are located upstream of the Shine-Delgarno