Chapter 13 Molecular Basis Of Inheritance Flashcards

1
Q

In_______, Watson and Crick introduced a model for _______

A

1953, DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Hereditary information is encoded in

A

DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The role of DNA was worked out by studying_______ and the _______ that infected them

A

Bacteria, viruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Discovery of genetic of DNA began with research by _______ in _______

A

Frederick Griffith, 1928

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Griffith mixed heat heat killers remains of pathogenic strain with harmless strain and some living cells became pathogenic. He called this_____

A

Transformation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Chargaff’s Rules

A

The base composition of DNA varies between species

In any species the percentages of A and T bases are equal and the percentages of G and C bases are equal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Franklin used ______ to determine the molecular structure of DNA

A

X-ray crystallography

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Watson and Crick SemiConservative Model of Replication

A

Predicts that when a double helix replicates, each daughter molecule will have one old strand derived from the parent molecule and one newly made strand.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Conservative model

A

Two parent strands rejoin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Dispersive model

A

Each strand is a mix of old and new

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Replication begins at sites called _________, where the two DNA strands are separated, opening up a replication bubble

A

Origin of replication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

At each end of the bubble is a _________, a Y shaped region where the parents strands of DNA are being unwound

A

Replication fork

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Helicases

A

Are enzymes that untwist the double helix at the replication forks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Single strand binding proteins

A

Bind to and stabilize single stranded DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Topoisomerase

A

Relieves the strain caused by tight twisting ahead of the replication fork by breaking, swiveling, and rejoining DNA strands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

The initial strand is a short RNA

A

Primer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

DNA polymerase cannot initiate_______ of a polynucleotide, they can only add nucleotides to an already existing chain base paired with the template

A

Synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The enzyme_______, starts an RNA chain with a single RNA nucleotide and adds RNA nucleotides one at a time using the parent DNA as a template

A

Primase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

The new DNA strand will start from the

A

3’ end of the RNA primer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Enzymes called_________, catalyze the elongation of new DNA at a replication fork

A

DNA polymerases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The rate of elongation is about _____ nucleotides per second I’m bacteria and ______ per second in human cells

A

500,50

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

dATP is

A

Used to make DNA and is similar to the ATP of energy metabolism

The difference is in the sugars: dATP has deoxyribose and ATP has ribose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

As each monomer nucleotide joins the DNA strand,

A

It loses two phosphate groups as a molecule of pyrophosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Newly formed DNA strands must be formed _______ to the template strand

A

Antiparallel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

DNA polymerase add nucleotides only in the free 3’ end of a growing strand. Therefore a new DNA strand can only elongate in the

A

5’ to 3’ direction

26
Q

Leading strand

A

DNA polymerase synthesizes moving toward the replication fork

27
Q

To elongate the other new strand, the ___________, DNA polymerase must work in the direction away from the replication fork

A

Lagging strand

28
Q

The lagging strand is synthesized as a series of segments called

A

Okazaki fragments

29
Q

After formation of Okazaki fragments, DNA polymerase removes

A

The RNA primers and replaces the nucleotides with DNA

30
Q

The remaining gaps are joined together by

A

DNA ligase

31
Q

The proteins that participate in DNA replication form a large complex

A

DNA replication machine

32
Q

__________ proofread newly made DNA, replacing any incorrect nucleotides

A

DNA polymerase

33
Q

In________ of DNA, other enzymes correct errors in base pairing

A

Mismatch repair

34
Q

For linear DNA, the usual replication machinery cannot complete

A

The 5’ ends of daughter strands

35
Q

Repeated rounds of replication produce shorter DNA molecules with

A

Uneven ends

36
Q

Eukaryotic chromosomal DNA molecules have special nucleotide sequences at their ends called

A

Telomeres

37
Q

Telomeres typically consist of

A

Multiple repetitions of one short nucleotide sequence

Telomeres do not prevent the shortening of DNA molecules but they do postpone it

38
Q

An enzyme called_________ catalyzes the lengthening of telomeres in __________

A

Telomerase, germ cells

39
Q

Telomerase is not active in most

A

Human somatic cells

40
Q

In a bacterium, the DNA is supercoiled and found in a region of the cell called the

A

Nucleoid

41
Q

A complex of DNA and protein found in the nucleus of eukaryotic cells

A

Chromatin

42
Q

Proteins called________ are responsible for the first level of DNA packing in ________

A

Histones, chromatin

43
Q

Four common types of histones

A

H2A, H2B, H3 and H4

44
Q

A__________ consists of DNA wound twice around a protein core of eight histones, two of each of the main histone types

A

Nucleosome

45
Q

The condensed chromatin is called___________, leas compacted chromatin is called

A

Heterochromatin, euchromatin

46
Q

Nucleic Acid Hybridization

A

The base pairing of one strand of a nucleic Acid to another complementary sequence

47
Q

Genetic Engineering

A

The direct manipulation of genes for practical purposes

48
Q

Plasmids

A

Small circular DNA molecules that replicate separately from the bacterial chromosome

49
Q

Recombinant DNA

A

Result of inserting foreign DNA into a plasmid

50
Q

Production of multiple copies of a single gene

A

Gene cloning

51
Q

The plasmid that carries the cloned DNA is called

A

Cloning vector

52
Q

Bacterial Restriction Enzymes

A

Cut DNA molecules at specific DNA sequences called restriction sites

53
Q

A restriction enzyme usually makes many cuts yielding

A

Restriction fragments

54
Q

Sticky ends

A

Cleaves DNA in a staggered manner. Sticky ends can bind with other complementary sticky ends

55
Q

Gel electrophoresis

A

Separates a mixture of nucleic Acid fragments based on length

56
Q

Polymerase Chain Reaction

A

Can produce many copies of a specific target segment of DNA

57
Q

The key to Polymerase Chain Reaction is an unusual heat stable DNA polymerase called

A

Taq Polymerase

58
Q

Once a gene is cloned, complementary base pairing can be used to determine the genes complete nucleotide sequence in a process called

A

DNA sequencing

59
Q

Purines

A

Two carbon nitrogen ring bases

Adenine and Guanine

60
Q

Pyrimidines

A

One carbon nitrogen ring bases

Thymine and Cytosine