DNA Replication

Question 0

Guanine base pairing

Answer 0

Only with cytosine

3 hydrogen bonds

Question 1

Adenine base pairing

Answer 1

Only with Thymine

2 hydrogen bonds

Question 2

Conservative model

Answer 2

Parent strand reforms after replication

Question 3

Dispersive model

Answer 3

New strand contains old and new fragments

Question 4

Semi-conservative model

Answer 4

Each newly synthesized helix contains one new and one old strand
Correct model

Question 5

Replication bubble

Answer 5

Proteins attach to DNA and separate strands

Question 6

Nucleoside triphosphate

Answer 6

Energy for DNA polymerase
Sugar and nitrogenous base plus 3 phosphate groups
2 phosphates get clipped off- undergo hydrolysis to create energy

Question 7

DNA polymerase III

Answer 7

Adds nucleotides to free 3’ end of DNA strand

Question 8

Okazaki fragments

Answer 8

Sections of newly synthesized DNA

Formed on lagging strand

Question 9

DNA ligase

Answer 9

Forms bonds between Okazaki fragments, joining them together

Question 10

Primer

Answer 10

Short strand of RNA that DNA pol III adds nucleotides to

Question 11

Primase

Answer 11

Joins RNA nucleotides to make primer that is complementary to DNA strand

Question 12

DNA polymerase I

Answer 12

Replaces RNA primer with primers of DNA nucleotides

Question 13

Helicase

Answer 13

Enzymes that untwists DNA helix @ replication fork

Question 14

Topoisomerase

Answer 14

Relieves strain caused by helicase as it unwinds DNA

Question 15

Single-strand binding protein

Answer 15

Binds to unpaired DNA template strands that helicase has unwound, stabilizing them

Question 16

Nuclease

Answer 16

Excises incorrect nucleotides

Question 17

Telomeres

Answer 17

Short repetitions of DNA sequence
Complete 5’ end of DNA
Short in old or cultured cells
Longer in germ cells that give rise to gametes

Question 18

Telomerase

Answer 18

Catalyzes lengthening of telomeres
Active in germ cells but not in somatic cells
Activated by some types of cancer cells