UNIT 3 2D: Gene structure and expression

Question 1

Coding Region

Answer 1

The exons of a gene that codes for the specific protein to be synthesised

Question 2

Operator

Answer 2

A section of DNA code where the repressor protein can bind

Question 3

Repressor

Answer 3

A regulatory protein that binds to DNA, inhibiting transcription

Question 4

Regulatory Gene

Answer 4

A region of DNA that codes for a regulatory protein, which controls the expression of other genes

Question 5

Structural gene

Answer 5

A region of DNA that codes for a protein that performs a specific function for a cell or organism and is not involved in the regulation of gene expression

Question 6

Operon

Answer 6

A series of genes under the control of a single promoter and operator

Question 7

Describe process of attenuation when trp levels are high

Answer 7

Ribosome does not pause at the 2 trp codons in the mRNA sequence
Terminator hairpin loop forms
RNA polymerase detaches from the DNA so transcription of trpE to trp A structural genes is terminated
Ribosome detaches from attenuator mRNA so trpE to trpA enzymes are not produced