AP Bio Operons

Match the following genetic regions to their roles:

• Genes of Operon

• The on/off switch where the repressor protein binds

• Operator

• Codes for the main protein / enzymes

• Promotor

• Place where transcription begins

• Regulatory gene

• Makes a repressor protein

The trp operon in E. Coli is responsible for making 5 polypeptides involved in the tryptophan synthesis pathway. When tryptophan is present, it combines with the repressor protein to block the operator. What type of operon is trp?

• Repressible

• Inducible

The operon model was discovered in E. Coli and is almost exclusively found in ​ (a)   .

• prokaryotes
• eukaryotes

The "on/off" switch for an operon is called the

• promoter
• repressor
• operator
• gene

For a repressible operon to be transcribed, which of the following must be true?

• A corepressor must be present.
• RNA polymerase and the active repressor must be present.
• RNA polymerase must bind to the promoter, and the repressor must be inactive.
• RNA polymerase cannot be present, and the repressor must be inactive.

Which of the following statements regarding the trp operon is true?

• The operator region produces the mRNA that codes for the repressor.

• The regulatory gene is not transcribed in the presence of the repressor.

• Repressor proteins are inactivated by the presence of the repressor. .

• The trp operon is always activated unless deactivated by a repressor

What is 1 in the diagram?

• RNA polymerase

• Inducer

• Repressor

• Operator

Tags

NGSS.HS-LS1-1

What is 2 in the diagram?

• RNA polymerase

• Inducer

• Repressor

• Operator

What is 4 in the diagram?

• RNA polymerase

• Inducer

• Repressor

• Operator

Which type of operon is shown in the image?

• inducible operon
• repressible operon
• positive control operon
• can't determine this from the image