The Molecular Basis of Inheritance (3)

Question 1

DNA strands are

Answer 1

Complimentary

Question 2

Complementary strands

Answer 2

Each strand of DNA has the information it needs to make the other strand because of Chargaff‘s rule

Question 3

Replication

Answer 3

 duplication process of DNA The DNA molecule splits into two strands and produces two complementary strands

Question 4

How many steps are there in replication

Answer 4

2

Question 5

 What is the first step of replication

Answer 5

Two strands of DNA are separated forming to replication forks

Question 6

What is the second step of replication

Answer 6

as the new strand forms new bases are added following the rules of base pairing

Question 7

Replication is carried out by

Answer 7

Enzymes

Question 8

What is the principal enzyme of replication

Answer 8

DNA polymerase

Question 9

DNA polymerase

Answer 9

An enzyme that joins individual nucleotides to, produce a new strand of DNA produce sugar phosphate bonds, proofreads new strands

Question 10

Telomeres

Answer 10

DNA at the tips of chromosomes that are nonsensical so that you don’t need it and its just there to chop off and it extends at the 3’ side

Question 11

Telomerase

Answer 11

Special enzyme that adds short repeated DNA sequences to telomeres 

Question 12

What does telomerase do

Answer 12

Helps to prevent genes from being damaged your loss during replication in embryonic cells stem cells and other rapidly dividing cells

Question 13

Telomerase is often switched off in

Answer 13

Adult cells

Question 14

What form is DNA in in prokaryotes

Answer 14

Singular circular chromosome

Question 15

When does replication occur in prokaryotes

Answer 15

Replication occurs when regulatory proteins bind to a starting point on the chromosome they trigger s phase to occur

Question 16

In prokaryotes replication starts in____
spot

Answer 16

One

Question 17

In what direction does replication occur in prokaryotes

Answer 17

Replication starts in one spot and proceeds in opposite directions

Question 18

What happens after replication in prokaryotes

Answer 18

Often to DNA attach to different sides of the cell and separate during cytokinesis

Question 19

How is DNA stored in eukaryotes

Answer 19

Tightly package with histones to form chromatin which is stored in the nucleus

Question 20

Where does replication begin on DNA

Answer 20

Replication may begin at many places on DNA

Question 21

In what direction is replication occur in eukaryotes

Answer 21

Replication can start in many spots and proceed in opposite directions

Question 22

Damaged regions of DNA sometimes copied which may…

Answer 22

Alter certain genes

Question 23

Semiconservative DNA replication

Answer 23

When DNA replicates the new DNA is made up of one daughter and one parent DNA strand

Question 24

How many problems does DNA polymerase have

Answer 24

3

Question 25

What is the first problem of DNA polymerase

Answer 25

DNA polymerase cannot start a new strand enough unless there is an existing nucleotide in place

Question 26

What is the solution to the first problem of DNA Polymerase

Answer 26

Primase

Question 27

Primase

Answer 27

Enzyme that puts down and RNA primer so that DNA polymerase can build the rest of the strand

Question 28

What is the second problem of DNA polymerase

Answer 28

DNA polymerase can only work in a five prime to three prime direction

Question 29

What is the solution to the second DNA polymerase problem

Answer 29

Okazaki fragments

Question 30

How do Okazaki fragments work

Answer 30

Okazaki fragments form starting from about 100 to 200 base pairs away from the RNA primer

Question 31

After Okazaki fragments form DNA polymerase takes away

Answer 31

The primer

Question 32

What connects Okazaki fragments

Answer 32

DNA ligase

Question 33

How does DNA ligase connect Okazaki fragments

Answer 33

DNA ligase connects the Okazaki fragments fragments by forming covalent bonds between the sugar and phosphate groups

Question 34

The strand that goes from 3 prime to 5 prime is called the

Answer 34

Leading strand

Question 35

The strand going from 5 Prime to 3 prime is called the

Answer 35

Lagging strand

Question 36

What is the third problem of DNA polymerase

Answer 36

Every time the DNA replicates DNA gets shorter because when the DNA polymerase takes away the primer there is nothing to replace it

Question 37

What is the solution to the third problem of DNA polymerase

Answer 37

Telomerase produces telomeres which are useful so when the DNA strands shorten you are not losing useful DNA

Question 38

The telomeres produced by telomerase are

Answer 38

Nonsensical Nucleotides are just there so but don’t affect anything

Question 39

when does replication occur

Answer 39

occurs during s phase in interphase

Question 40

Conservative model of DNA

Answer 40

the parental double helix remains intact and al new copy is made PARENT / \ PARENT NEW / \ / \ Parent New New New

Question 41

Semiconservativemodel of DNA

Answer 41

the two strands of the parental molecule separate and each function as a template for synthesis of a new complementary strand PARENT / \ both both / \ / \ both New New both

Question 42

Dispersive model of DNA

Answer 42

each strand is made of both daughter and parent strands in odd newly synthesized parts PARENT / \ mix mix / \ / \ mix mix mix mix

Question 43

heterochromatin

Answer 43

loops on scaffold proiten

Question 44

euchromatin

Answer 44

most unwound form of DNA -- js the nucleosomes together

Question 45

origin of replication

Answer 45

where they get the signal thingie and where the replication forks form

Question 46

replication bubble

Answer 46

the whole replication bubble thing

Question 47

how many replication bubbles does a prokaryote have

Answer 47

one

Question 48

how many replication bubbles do eukaryotes have

Answer 48

multiple

Question 49

Helicase

Answer 49

the enzyme that separates the strands and starts the bubble

Question 50

single strand binding proteins

Answer 50

proteins that temporarily block bases so that they can't attract each other -- they do this by preventing H bonds

Question 51

Topoisomerase

Answer 51

alleviate stress on the DNA bc as the helicase unwinds the DNA bc it builds up stress (imagine pulling a rope part) by cutting and putting back DNA so that helicase can keep doing its thang

Question 52

why is the lagging strand called a lagging strand

Answer 52

bc of okazaki fragments

Question 53

how do you get energy for polymerization

Answer 53

all of the bases start as ATP, GTP, etc. so when the 2 phoshates break off to provide energy

Question 54

how are the 5' and 3' end determined

Answer 54

the one with the 5 carbon standing up is the 5' side and vice versa for 3'

Question 55

lagging grows ____ separation

Answer 55

away

Question 56

leading grows ____ separation

Answer 56

towards

Question 57

after a new daughter strand is made what happens to the RNA primer

Answer 57

it leaves bc it doesn't mix with DNA properly

Question 58

mismatch repair

Answer 58

enzymes that check DNA, look for mistakes, change, and sometimes they cause mistakes bc they remove the wrong thing

Question 59

nucleotide excision repair

Answer 59

enzymes that cut out some segments of DNA and polymerasge adds good bases by gluing them with ligase and for larger mistakes they add a thymine dimers which distorts the DNA in order to break it and add the good DNA

Question 60

which side of the DNA is always shorter and why

Answer 60

5' end bc nonsense side so it gets shorter during every replication