Eukaryotic gene Regulation

The mechanism of gene regulation that does not involve changes to the DNA sequence but to the way in which DNA is packed is called

• Transcription

• Imprinting

• Alternative splicing

• Epigenetics

The sex - specific silencing of gene expression is known as

• Transcription

• Alternative Splicing

• Imprinting

• Translation

The process by which a single primary RNA transcript is used to make multiple proteins is called

• Transcription

• Imprinting

• Alternative splicing

• Epigenetics

Histone de-acetylases (H D A Cs) are enzymes that remove acetyl groups from histone proteins. With regard to their effects on transcription, H D A Cs should do which of the following?

• activate transcription by opening chromatin

• activate transcription by condensing chromatin

• repress transcription by opening chromatin

• repress transcription by condensing chromatin

Histone modification

• is fixed; once a histone is modified it stays that way and the genes with which it is associated are turned on or off permanently

• is fixed, but this has no effect on whether genes are expressed

• is random- sometimes the lysines are modified and sometimes they're not, but the state is independent of the environment or cell types

• can change over time in response to environmental clues, allowing genes to be turned on or off as needed

What type(s) of molecule(s) are enhancers?

• DNA

• RNA

• Protein

• Lipid membrane

What type(s) of molecule(s) are transcription factors?

• DNA

• RNA

• Protein

• Lipid membrane

Enhancers can affect transcription at promoters many thousands of base pairs away. How is this thought to be accomplished?

• Enhancers send activating signals to the promoter directly through D N A.

• Enhancers directly contact promoters with the intervening D N A looping out.

• Proteins bound to enhancers interact with proteins bound to the promoter with D N A looping out.

• Enhancers unwind chromatin.

Why is a myosin gene transcriptionally expressed in muscle cells but not in neurons?

• Neurons lack an enhancer in the myosin gene.

• Neurons lack the myosin gene.

• Muscle cells have an extra enhancer in the myosin gene.

• Muscle cells express an activator protein that binds the myosin enhancer.

Tags

NGSS.HS-LS1-4

A eukaryotic gene has a pre-m R N A with five exons (1, 2, 3, 4, 5). Which of the following arrangements of exons is not possible in a mature m R N A due to alternative splicing? There are two correct answers.

• 1, 2, 5

• 1, 3, 4, 5

• 1, 3, 2, 4, 5

• 1, 3, 3, 5