Section 3-1: DNA structure & replication

Question 1

3 components of DNA

Answer 1

1. sugar (deoxyribose)
2. phosphate group
3. nitrogenous base

Question 2

4 components in nitrogenous base

Answer 2

purines: adenine (A) and guanine (G)
pyrimidines: thymine (T) and cytosine (C)

Question 3

do A and T or G and C have stronger interaction?

Answer 3

G and C, 3 H bonds vs A and T, 2 H bonds

Question 4

3 components of DNA double helix structure

Answer 4

base pairing (hydrogen bonds)
sugar-phosphate backbone
5’ to 3’ direction, antiparallel and complementary

Question 5

all cells in the same organism have the same…

Answer 5

DNA

Question 6

DNA replication

Answer 6

making exact copies of itself during cell division
each daughter cell gets original and new DNA strands

Question 7

what happens when DNA repair enzymes don’t fix mistakes?

Answer 7

unfixed mistakes create mutations

Question 8

DNA replication starts from

Answer 8

replication origins (AT rich)

Question 9

DNA replication uses (substrates)

Answer 9

dATP, dTTP, dGTP, dCTP

Question 10

DNA replication catalyzed by

Answer 10

DNA polymerase: proofreading, elongation from 5’ to 3’

Question 11

DNA repair enzymes

Answer 11

fix mistakes during replication