Exam 16: Regulation of Gene Expression

The expression of the lac structural genes is _______ when lactose is absent from the culture medium and is _______ when lactose is added, because lactose binds to the _______ and inactivates it.

A retrovirus, but not other RNA viruses, can be targeted through drugs that inhibit _______.

Which scenario would most support a hypothesis that the environment plays little or no role in epigenetic modifications?

The activity of _______ tends to lead to increased transcription.

Actin, which is part of many cellular structures and has several functions, is produced at constant levels in nearly all cells.It is best described as a(n) _______ protein.

In comparison with structural genes in bacterial operons, genes that encode for stress responses in plants

Which stage of regulatory control in eukaryotes largely occurs in the cytoplasm, outside the nucleus?

In DNA replication, 5-methylcytosine base-pairs with

If each interphase nucleus in 100 epithelial cells from a rat contains a single Barr body, one can conclude that

A mutation causes an increase in the production of the enzyme DNA demethylase.This will most likely lead to _______ methylation and an overall _______ in gene expression.

Drugs that affect miRNA and siRNA expression might be useful for cancer, since they affect _______.

When an enhancer is bound, it

A virus that kills hosts and spreads quickly likely enters the _______ cycle immediately.

A bacterium prefers to metabolize fructose.If fructose is present in high concentrations, the production of enzymes involved in breaking down other sugars ceases.This is an example of

A mutant strain of bacteria will produce the structural enzymes in the lac operon regardless of the concentrations of glucose or lactose.Most likely, this strain is defective in the _______ gene.

Which AIDS treatment works by preventing the synthesis of viral DNA?

Lytic bacterial viruses

The expression of some genes can be regulated in part by the pattern of RNA splicing.This is an example of

In its role in transcription regulation, TFIID binds first to _______ and later to _______.

Nucleosomes disaggregate (or "open") to allow transcription and then reaggregate