Join thousands of students who trust us to help them ace their exams!Watch the first video
Multiple Choice
Which functional group is present in the structure of the lac repressor that allows it to bind to the operator site within the lac operon?
A
Hydroxyl
B
Carboxyl
C
Amide
D
DNA-binding domain
Verified step by step guidance
1
Understand the context: The lac repressor is a protein that regulates the lac operon in bacteria. It binds to the operator site to inhibit transcription.
Identify the role of functional groups: Functional groups in proteins, such as the DNA-binding domain, are crucial for interactions with DNA.
Recognize the DNA-binding domain: This domain typically contains specific structural motifs, such as helix-turn-helix, zinc finger, or leucine zipper, which facilitate binding to DNA.
Differentiate from other functional groups: Hydroxyl, carboxyl, and amide groups are common in proteins but are not specifically responsible for DNA binding.
Conclude that the DNA-binding domain, rather than the individual functional groups listed, is responsible for the lac repressor's ability to bind to the operator site.