Final Exam Review Ch. 15, 16, & 19

Front

What is a transition mutation in DNA?

Back

A transition mutation is a substitution of one purine for another purine (A <-> G) or one pyrimidine for another pyrimidine (C <-> T).

Front

What is the role of enhancers in eukaryotic gene expression?

Back

Enhancers are regulatory sequences that bind transcription factors to activate or increase the rate of transcription.

Front

What must assemble on the chromosome before RNA polymerase II can bind to the promoter?

Back

General transcription factors must assemble on the chromosome before RNA polymerase II can bind to the promoter.

Front

What is an example of a transversion mutation?

Back

A transversion mutation is a substitution of a purine for a pyrimidine or vice versa, such as Adenine (A) to Thymine (T).

Front

How is the trp operon described in terms of its functional state?

Back

The trp operon is always activated unless repressed.

Front

What is a purine?

Back

Purines are nitrogenous bases that include adenine (A) and guanine (G).

Front

What is a pyrimidine?

Back

Pyrimidines are nitrogenous bases that include cytosine (C), thymine (T), and uracil (U).

Front

What is the function of transcription factors?

Back

Transcription factors are proteins that help regulate the transcription of DNA into RNA by binding to specific DNA sequences.

Front

What is the significance of the promoter region in gene expression?

Back

The promoter region is a specific sequence of DNA where RNA polymerase binds to initiate transcription.

Front

What is the difference between an enhancer and a silencer?

Back

Enhancers increase the rate of transcription, while silencers decrease or repress transcription.