Genome diversity and Chromosomes

Question 1

Genome

Answer 1

sequence of nucleotides in DNA that comprises the eugenic makeup of an organism

Question 2

Genome size

Answer 2

the total amount of DNA contained within one copy of a single genome
~ always refers to haploid DNA content

Question 3

C-value Paradox

Answer 3

large genome size and increased genome complexity do not always correlate
e.g. transposable elements

Question 4

Transposable elements

Answer 4

pieces of DNA that copy themselves within a genome and lead to increases in genome size

Question 5

Intergenic regions

Answer 5

bits between genes that do no appear o contain ‘typical’ gene units
a.k.a. junk DNA

Question 6

Gene

Answer 6

region that controls a discrete hereditary characteristic, usually a protein

Question 7

Bacterial NAPS

Answer 7

Bacterial Nucleoid Associated Proteins

Question 8

IHF

Answer 8

Integration Host Factor

Question 9

Histone

Answer 9

~ basic binding proteins

~ histone forms an octamer which contains two of each of the four core histones (H2A, H2B, H3 and H4)

Question 10

Nucleosome

Answer 10

DNA wrapped around a histone complex in a left-handed manner

Question 11

Euchromatin

Answer 11

chromatin in relatively decondensed regions
~ stians lightly
~actively transcribes genes

Question 12

Heterochromatin

Answer 12

chromatin in more compact regions
~ stains darker
~ less active transcription

Question 13

Histone acetyltransferases (HATs)

Answer 13

add acetyl groups to lysine side chains

Question 14

Histone deacetylases (HDACs)

Answer 14

removes acetyl groups

Question 15

Histone methyltransferase (HMTs)

Answer 15

add methyl groups to lysine and arginine side chains

Question 16

Histone demethylases

Answer 16

removes methyl groups

Question 17

Phosphates

Answer 17

~ added by kinases

~ removed by phosphatases

Question 18

Ubiquitin

Answer 18

added to histones by a chain of enzymatic reactions and removed by a deubiquitinating enzyme

Question 19

Chromodomains

Answer 19

bind to specific methylated lysine and are often associated with transcriptional silencing

Question 20

Centromere

Answer 20

a heterochromatic region and is inherited epigenetically
~ definded by presence of CENP-A
~ can be point or regional centromeres

Question 21

Point centromere

Answer 21

very small and have defined sequences

Question 22

Regional centromere

Answer 22

hundreds of kb long

Question 23

CENP-A

Answer 23

histone H3 specific nucleosome that contains H3 variant