Epigenetics

Question 1

The changes in gene expression or phenotype that are potentially heritable without altering the underlying DNA base sequence is called

Answer 1

Epigenetics

Question 2

what coined the term epigenetics

Answer 2

Conrad Waddington

Question 3

what molecular process lead to epigenetic changes

Answer 3

1.changes in chromatin structure altering gene expression
2. molecular mechanisms that alter chromatin structure.

Question 4

what is the addition of methyl groups to nucleotide bases

Answer 4

DNA methylation

Question 5

what is the most common methylation

Answer 5

methylation of cytosine to produce 5-methylcytosine

Question 6

methylation occurs in single or both DNA strands

Answer 6

both DNA strands

Question 7

what is a common epigenetic modification of chromatin

Answer 7

DNA methylation

Question 8

what is responsible for the differences in the phenotypes of honeybee queens and workers

Answer 8

Epigenetics in DNA methylation

Question 9

histone modification are on the tails or head that interact with DNA

Answer 9

tails

Question 10

histone modification affect

Answer 10

chromatin structure and gene transcription.

Question 11

the post-translational modification of histones are called

Answer 11

epigenetic marks / histone code

Question 12

Post translational modifications inludes

Answer 12

addition of phosphates, methyl groups, acetyl groups, ubiquitin

Question 13

Acetylation of histones destabilizes the chromatin which affects transcription in what way

Answer 13

increased transcription

Question 14

deacylation affects transcription in what way

Answer 14

decreases transcription

Question 15

what histones are associated with active transcription

Answer 15

H3 K4 Me3 AND H3 K36 Me3

Question 16

what histones are associated with transcriptional repression

Answer 16

H3 K9 Me3 and H4 K20 Me3

Question 17

effect of hypoacetylated lysine on transcription

Answer 17

repression

Question 18

effect of acetylated lysine on transcription

Answer 18

activated

Question 19

effect of methylated lysine on transcription

Answer 19

activation, elongation, repression

Question 20

effect of methylated arginine on transcription

Answer 20

activation

Question 21

effect of ubiquitinylated lysine on transcription

Answer 21

activation, repression

Question 22

do single histone modifications individually determine the transcriptional activity of a gene. true/false

Answer 22

false, it is the combined presence of a multiple epigenetic marks

Question 23

explain crosstalk

Answer 23

cross talk between epigenetics such that one histone mark may affect whether additional marks occur nearby and how they finction

Question 24

why do crosstalks occur?

Answer 24

because epigenetic marks recruit enzymes and protein that modify other histone

Question 25

Epigenetic effects by

Answer 25

RNA molecules

Question 26

an interaction between two alleles that leads to a heritable change in expression of one of the alleles

Answer 26

Paramutation

Question 27

explain paramutation in corn

Answer 27

a copy of the B' allele converts the B-I allele to B'*, which has the same phenotype as B'

Question 28

pigmentation of b1 corn locus

Answer 28

B-I B-I produces a pigmented plant B' B' and B' B* lightly pigmented

Question 29

paramutation in Kit locus in mice

Answer 29

a cross between kit+Kit+ and kit+kit t produces some kit+kit+ with phenotypes of Kit+ kit+ and kit+kit t

Question 30

life experiences, especially early in life having long-lasting effects on behavior is called

Answer 30

bahvioral epigenetics

Question 31

Effects of epigenetics

Answer 31

behavioral epigenetics changes induced by maternal behavior early stress in humans in cognition environmental chemicals

Question 32

licking and grooming of offsprings in rodents affects

Answer 32

DNA methylation

Question 33

childhood abuse leads to

Answer 33

more methylation of glucocorticoid receptor gene

Question 34

histone acetylation in mice improved

Answer 34

learning and memory in mice with a Alzheimer like disorder

Question 35

what is the effect of maternal behavior in mice

Answer 35

alters the expression of stress-response genes which makes them less fearful as adult

Question 36

what fungicide acts as an endocrine disruptot increasing DNA methylation in sperm

Answer 36

vinclozin (prevented sperm production in treated animals)

Question 37

the offsprings of males on the low protein diet has

Answer 37

increased expression of genes involved in lipid and cholesterol metabolism and differences in DNA methylation

Question 38

explain epigenetic effects in monozygotic twins

Answer 38

methylation and acetylation patterns were similar in early life but older twins are different in gene expression

Question 39

how is X inactivation a type of epigenetics

Answer 39

x inactivation results in a stabel change in gene expression that is passed on to daughter cells

Question 40

X-inactivation starts at

Answer 40

X inactivation center and spreads to the remainder of the X chromosome

Question 41

what gene on the inactive X produces an long noncoding RNA that coats the inactive X chromosome and suppress transcription

Answer 41

Xist gene

Question 42

what gene inhibits transcription of Xist on active chromosome

Answer 42

Tsix

Question 43

what gene stimulates trasncription of Xist on inactive X chromosome

Answer 43

Jpx

Question 44

what gene sustains Tsix exoression on active X, which inhibits Xist and maintains transcription

Answer 44

Xite

Question 45

stem cells are undifferentiatec cells that can generate every cell type in an organism, this property is called

Answer 45

Pluripotency

Question 46

gene expression profile during cell differentiation is

Answer 46

increasingly fixed

Question 47

the transcription factors that induce pluripotency causes

Answer 47

extensive epigenetic reprogramming which alters patterns of DNA methylation and histone modifications

Question 48

effect of reprogramming differentiated adult cells forms

Answer 48

induced pluripotent stem cells (iPCSs)

Question 49

epigenetics in genomic imprinting

Answer 49

the expression of an allele depends on whether it is inherited from male or female parents

Question 50

what is the overall pattern of chromatin modification possessed by each individual organism

Answer 50

Epigenome

Question 51

what are used to detect DNA methylation

Answer 51

restriction endonucleases bisulfate sequencing

Question 52

waht is used to detect histone modifications

Answer 52

ChIP

Question 53

what can be used to determine the locations of 5-methylcytosines

Answer 53

bisulfate sequencing