DNA Duplication

Question 1

DNA Duplication occurs

Answer 1

in the S Phase

Question 2

DNA Duplication

Answer 2

2 complementary DNA strands are unzipped and a new complementary strand of each original strand is constructed

Question 3

Helicase

Answer 3

uses ATP to untwist DNA and separate double strands

Question 4

DNA Polymerase

Answer 4

follows helicase and makes new strands

Question 5

Mismatch Repair

Answer 5

DNA polymerase proofreads work as it progresses by comparing old and new strands

Question 6

Leading Strand

Answer 6

DNA polymerase synthesizes it continuously towards fork

Question 7

Lagging Strand

Answer 7

DNA polymerase synthesizes it in opposite direction

Question 8

DNA Polymerase reads old strand from

Answer 8

3’ to 5’

Question 9

DNA Polymerase reads new strand from

Answer 9

5’ to 3’

Question 10

Discontinuous replication

Answer 10

Reads new and old strand in different directions and then moves back to the fork

Question 11

Telomeres

Answer 11

Stretches of non-coding DNA at the ends of eukaryotic chromosomes that are molecular clocks that encode a persons lifespan

Question 12

How many telomeres are lost each time a cell divides in humans?

Answer 12

16 blocks of TTAGGG

Question 13

Why are telomeres a molecular clock?

Answer 13

DNA polymerase cannot copy the last stretch of bases at the end of chromosomes and when the length of telomeres shorten mitosis slows causing the cell to go into senescence (old age)

Question 14

Telomerase

Answer 14

Found in immortal cells, it adds TTAGGGs during each S phase so the telomeres never shorten

Question 15

Examples of types of cells with telomerase

Answer 15

stem cells and cancer cells

Question 16

Progeria

Answer 16

Disease where kids age at an extremely accelerated rate, most die around 13 years old from “old age” disease such as heart problems and cancer, born with the telomeres of an 80 year old