exam 1d

Question 1

3 components of a nucleotide

Answer 1

ribose (sugar), base, phosphate

Question 2

DNA backbone is formed by

Answer 2

sugar and phosphate groups

Question 3

purines

Answer 3

A and G

Question 4

pyrimidines

Answer 4

C and T

Question 5

DNA karyotyping

Answer 5

technique that allows researchers observe any abnormality in chromosomes

Question 6

gene

Answer 6

is a segment of DNA that contains the instruction to make a particular protein or RNA molecule

Question 7

introns

Answer 7

unlike exons, intron sequences do not code for proteins. Intron play a regulatory role in gene expression

Question 8

DNA replication and separation

Answer 8

DNA replicated in the interphase of the cell cycle, while the replicated DNA is separated in the mitosis phase of the cell cycle

Question 9

telomere

Answer 9

a compound structure at the end of a chromosome

Question 10

replication origin

Answer 10

particular sequence in a genome at which replication is initiated

Question 11

centromere

Answer 11

the region of a chromosome to which the microtubules of the spindle attach, via the kinetochore, during cell division.

Question 12

nucleosomes

Answer 12

are formed to compact DNA and that histone proteins are involved in the formation of nucleosomes

Question 13

histone tails

Answer 13

are subjected to many chemical modifications to regulate the binding between the histone proteins and DNA, which in turn regulate gene expression

Question 14

different levels of chromosome packing

Answer 14

nucleosome, chromatin fiber, loop

Question 15

different combinations of histone tail modifications can

Answer 15

confer a specific meaning on the stretch of chromatin on which they occur