Gene expression

What are the parts in the DNA sequence of an operon?

An operon is composed of a promoter, an operator, and the structural genes. They must occur in that order.

________ brings an enhancer into contact with transcription factors and other proteins to increase transcription.

DNA bending protein

Which of the following is FALSE regarding RNA stability?

RNA has a set lifespan which allows for the production of all proteins to always occur for the same amount of time before RNA degradation

The binding of ________ is required for transcription to start.

RNA polymerase

Gene regulation happens in many steps throughout protein synthesis. Which of the following regulatory processes happens FIRST before all of the others?

RNA splicing

The rate at which RNA decays is known as ________.

RNA stability

In females, one of the two X chromosomes is inactivated during embryonic development because of epigenetic changes to the chromatin. What impact do you think these changes would have on nucleosome packing?

The nucleosomes would pack more tightly together.

What types of regulatory molecules are there?

There are three types of regulatory molecules: repressors, activators, and inducers.

All of the following organisms are capable of gene regulation at the transcriptional and translational level EXCEPT which one?

a bacterial cell

Much of gene regulation occurs during transcription with the help of transcription factors. Which of the following would result in an increase in transcription?

a transcription factor binding to an enhancer region

If a prokaryotic cell is in need of a protein it will need the help of a ________ to bind to the promoter in order to begin transcription via positive gene regulation.

activator

Prokaryotes produce proteins for a variety of different functions. In the presence of an external stimulus a prokaryote will either want to produce a specific protein which it is lacking or halt production of that protein if it is already present in the external environment. Regardless of the needs of the cell, what molecule is required first before the cell can either begin or prevent transcription from happening?

an inducer

Gene expression is ________.

both transcription and translation

A(n) ________ element is next to the gene being transcribed on the same chromosome.

cis-acting

Gene products that are needed consistently are ________ in prokaryotes.

constitutively expressed

Which of the following are involved in post-transcriptional control?

control of RNA splicing and shuttling, and stability

The key to epigenetic regulation is ________.

controlling accessibility to transcription factors and RNA polymerase binding

Binding of an RNA binding protein will ________ the stability of the RNA molecule.

either increase or decrease

Changes in gene regulation that are caused by modifications to histones and the DNA, but not the nucleotide sequence itself, are known as ________.

epigenetic

Control of gene expression in eukaryotic cells occurs at which level(s)?

epigenetic, transcriptional, post-transcriptional, translation, and post-translational levels

________ gene regulation occurs from transcription beyond translation.

eukaryotic

________ is required to give cells unique specializations.

gene expression

Cells found in your brain have a different function than cells found in your pancreas or your kidneys yet they all have essentially the same DNA. Which of the following statements is FALSE regarding gene regulation?

gene regulation occurs only during transcription

In order for the lac operon to be triggered, lactose must be present and ________.

glucose stores depleted

The main role of the catabolite activator protein is to ________.

increase the binding ability of RNA polymerase to the lac operon promoter region

What will result from the binding of a transcription factor to an enhancer region?

increased transcription of a distant gene

Genes associated with metabolism of a specific substance, such as lactose, are typically contained on ________ operons.

inducible

Cells express different genes in response to ________.

internal triggers and external signals

________ play a role in destroying mRNA targets.

miRNAs

In prokaryotes, the trp operon is under ________ that ________ prevents RNA polymerase from binding.

negative regulation; physically

RNA splicing occurs in the ________.

nucleus

In prokaryotes, structural proteins in a single biochemical pathway are usually found as a(n) ________ within the genome.

operon

In ________, transcription and translation occur simultaneously.

prokaryotes

Post-translational control refers to the:

regulation of gene expression after translation

If glucose is absent, but so is lactose, the lac operon will be ________.

repressed

________ operons typically contain genes encoding components in biosynthetic pathways.

repressible

Protein synthesis begins in the cell with transcription when a cell is in need of a certain protein. Conversely, when a cell has enough of a certain protein or it is able to obtain it from the external environment then transcription of that protein will stop. Which of the following is responsible for turning off transcription when a cell no longer needs to produce a protein?

repressors

During epigenetic regulation histones are modified in order to aid in what process?

the opening and closing of certain chromosomal segments

Prokaryotic gene regulation occurs at the level of ________.

transcription

For transcription to begin in eukaryotes, ________ must bind the DNA first.

transcription factors

The ________ operon contains five genes that are switched off when tryptophan is present in the environment.

trp

The ________ of mRNA regulate localization, stability, and translation.

untranslated region