Environmental Effects and Epigenetics

Question 1

What are housekeeping genes?

Answer 1

Genes that are required for the maintenance of basic cellular function, and are expressed in all cells.

Question 2

What are histones?

Answer 2

Alkaline proteins that package DNA into nucleosomes (the structural units of chromosomes).

Question 3

What are transcriptional units composed of?

Answer 3

1 - Structural information (coding for protein).

2 - Regulatory sequences (instructions for expression).

Question 4

What are promotors?

Answer 4

Regulatory sequences that control transcription initiation to which RNA polymerase binds.

Question 5

What are enhancers?

Answer 5

Regulatory sequences that control the rate of transcription.

Question 6

List the histones that are contained in nucleosomes.

Answer 6

2x of:

H2A, H2B, H3, H4.

Question 7

What is the purpose of histone modification?

Answer 7

To turn genes on or off.

Question 8

How can histone modification be controlled?

Answer 8

Drugs and environmental factors modify inhibitors for histone-modifying enzymes.