DNA organization

Question 1

supercoiling

Answer 1

like the double coiling that forms on phone wires
-helps DNA to be even more compact

Question 2

link number (LK)

Answer 2

of base pairs/ bp per turn

Question 3

topoisomer

Answer 3

molecules with the same DNA, but different link number

Question 4

chromatin

Answer 4

clearly visible highly condensed DNA structure (DNA + histones)
-portion thicker in diameter

Question 5

histones

Answer 5

protein in which DNA wraps around
-this is what causes chromatin to form

Question 6

nucleosome

Answer 6

DNA wrapped around a histone core

Question 7

histone core

Answer 7

two copies of each of the following histone proteins: H2A, H2B, H3, and H4

Question 8

heterochromatin

Answer 8

more condensed chromatin region compared to euchromatin
-these levels of compaction are not permanent

Question 9

histone tails

Answer 9

act as “signaling antenas” and can affect gene expression by making modifications to chromatin structure

Question 10

chromosome-banding techniques

Answer 10

staining patterns of chromosomes that resemble bands around chromosomes
-aids in their identification and analysis for detecting abnormalities

Question 11

c-banding

Answer 11

identifies regions of heterochromatin particularly in the centromeric regions
-chromosome is denatured with heat
-stained with Gisemsa

Question 12

g-banding

Answer 12

most common form of banding
-staining with gisemsa for easier identification

Question 13

repetitive sequences

Answer 13

-functional genes like rRNA (moderately repetitive)
-noncoding sequences

Question 14

satellite DNA

Answer 14

regions of the genome with different GC content than the rest of the genome
-highly repetitive
-present as tandem repeats

Question 15

CEN regions

Answer 15

minimal region of centromere for function of chromosome segregation

Question 16

tandem repeats

Answer 16

the number varies by person
-important for DNA fingerprinting