Molecular Regulation

Question 1

Repressors:

Answer 1

bind to regulatory sequences in the DNA and

prevent transcription of target genes

Question 2

Activators:

Answer 2

bind to regulatory sequences in the DNA and

stimulate transcription of target genes

Question 3

co-repressor

Answer 3

Some must first bind a small ligand (binds to DNA and represses target gene)

Question 4

inducer

Answer 4

Most must first bind a small ligand (binds to regulatory sequence, removing ligand)

Question 5

Lac Operon

Answer 5

The Lac Operon is normally off
- In the absence of lactose, the repressor is made and binds at the operator loci
and blocks transcription of downstream structural genes by blocking the
promote

Question 6

Arg Operon

Answer 6

Arginine Operon

Question 7

Regulatory gene

Answer 7

encodes a repressor protein that represses (blocks) operon activity

Question 8

Control Region

Answer 8

Contains promoter (for transcription) and operator, which is
where the repressor protein binds

Question 9

Structural genes

Answer 9

Genes that are regulated together by the regulatory protein and control region
to provide the function of that operon

Question 10

Repressible

Answer 10

genes in an operon are turned OFF by the product that is synthesized