Chapter 6: Epigenetics And disease

Question 1

Occurs through the attachment of a methyl group to the carbon-5 position of cytosine

Answer 1

DNA Methylation

Question 2

A structure consisting of DNA tightly wound around histones into a condensed state and not actively transcribed

Answer 2

Heterochromatin

Question 3

Differences between the alleles active in two cells can confer two very different traits

Answer 3

Somatic mosaicism

Question 4

Positively charged proteins around which negatively charged DNA molecules are wound, facilitating compaction of DNA into the cellular nuclei

Answer 4

Histones

Question 5

A set of histones and the segment of DNA wound around them are together known as:

Answer 5

Nucleosomes

Question 6

When a DNA segment is bound tightly to its associated histones

Answer 6

Heterochromatic

Question 7

DNA that is loosely bound around histones

Answer 7

Dichromatic

Question 8

Sperm cells express not histones but

Answer 8

Protamines

Question 9

Each of the cells in the early embryo has the potential to give rise to a somatic cell of any type. This type of cell is called

Answer 9

Totipotent

Question 10

A small percentage of genes that are necessary for the function and maintenance of all cells

Answer 10

Housekeeping genes

Question 11

Both the maternal and paternal inherited copies contribute to offspring phenotype

Answer 11

Biallelic

Question 12

When the maternal copy is randomly chosen for inactivation in some somatic cells and the paternal copy is randomly chosen for inactivation in other somatic cells

Answer 12

Monoallelic

Question 13

Two diseases and that appear due to imprinting

Answer 13

Prader-Willi syndrome

Angleman syndrome

Question 14

The regulation of gene expression not caused by DNA sequence

Answer 14

Epigenetics

Question 15

_______ ________ leads to silencing of genes

Answer 15

DNA methylation

Question 16

The process of predictable gene silencing on one copy of a chromosome but not on the other, depending on which parent transmits the chromosome

Answer 16

Imprinting

Question 17

Carries the code for a protein to a ribosome

Answer 17

mRNA

Question 18

Can regulate gene expression

Answer 18

miRNA

Question 19

True or False: some epigenetic modifications can be reversed

Answer 19

TRUE

Question 20

Abnormal methylation of tumor suppressor genes may be a factor in (regression/progression) of specific types of cancer

Answer 20

Progression

Question 21

MicroRNAs that stimulate development and progression of cancer cells called:

Answer 21

Oncomirs

Question 22

Environmental chemicals, dietary factors, and alcohol intake can modify gene expression by causing __________ modifications.

Answer 22

Epigenetic