AP Biology Chapter 18 Part 1

A protein that binds to the enhancer or operator and blocks the RNA polymerase

• regulator

• repressor

• activator

• corepressor

What is the name of the stretch of DNA where RNA polymerase binds?

• operator
• promoter
• enhancer
• origin

Protein molecules around which DNA is tightly coiled in chromatin

• Histones
• Whey
• Casein
• Hemoglobin

The parts of a gene that do NOT code for amino acids in a protein are called

• introns
• exons
• codons
• anticodons

A chemical modification of DNA that does not affect the nucleotide sequence of a gene but makes that gene less likely to be expressed.

• methylation
• acetylation
• transcription
• translation

A cellular organelle that breaks down proteins marked with ubiquitin is a(n)

• proteosome
• mitochondria
• roughER
• golgi apparatus

Most gene regulation happens at which step along the way?

• translation
• transcription
• signal transduction
• DNA replication

RNA interference means short RNA sequences bind to ___ and prevent their translation.

• mRNA
• tRNA
• rRNA
• ribosomes

What is an exon?

• section of mRNA that codes for protein
• section of mRNA that does not code for protein
• section of tRNA that codes for protein
• section of rRNA that codes for protein

All of the following are true about DNA methylation EXCEPT

• takes place on the DNA
• enzymes add a methyl group
• when it occurs, transcription is more likely to occur
• chromatin becomes more tightly packed