Biology

The "on/off" switch for an operon is called the

• promoter
• repressor
• operator
• gene

what does a promoter do?

• it allows a gene to be transcribed
• it creates a DNA segment
• it is another word for ribosomes
• it is another word for RNA

what is an operon?

• a part of a ribsome
• a part of a Rna
• a unit made up of linked genes that code for proteins needed to do a specific task
• needed for dna replication

An operon consists of all the the following EXCEPT

• operator
• promoter
• regulatory gene
• genes of the operon

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

• regulator
• repressor
• activator
• corepressor

A small molecule that binds to a repressor and makes it active

• repressor
• regulator
• activator
• corepressor

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

All of the following are true about histone acetylation EXCEPT

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

In eukaryotes, distal control regions that activators bind to are called 

• enhancers
• promoters
• repressors
• transcription factors

In eukaryotes, proteins that help the RNA polymerase bind to the promoter for transcription

• transcription factors
• topoisomerase
• regulatory genes
• activators