Lecture 5 Flashcards
(154 cards)
1
Q
[Year] - [Scientist] concept of hereditary factor
-chemical composition was not yet known and understood
A
1865 - Gregor Mendel
2
Q
[1930] - [Scientist]
2 view points about genes
1. Gene is just a hypothetical entity
2. Gene could be a chemical compound
A
R.A. Fisher
3
Q
What are the three components that make up the chemical composition of a chromosome
A
Lipids, Proteins, and Nucleid
4
Q
A component of chromosome found in interphase chromosomes, metaphase chromosomes, and nucleic matrix
A
Lipids
5
Q
A type of protein which is responsible for packing the DNA (chromatid-chromosome)
A
Histones or Protamines
6
Q
a type of protein that make up the scaffold upon which chromatin loops are anchored
A
Non-histone chromosomal protein
7
Q
2 types of nucleic acid
A
DNA (deoxyribonucleic acid)
RNA (ribonucleic acid)
8
Q
DNA is the genetic material of all living organisms except for some _____
A
Viruses
9
Q
genetic material of some viruses
A
RNA
10
Q
What are the characteristics of a good genetic material according to H.J Miller
A
- Contain all the necessary biological information
- Mutation is duplicated
- Stable molecular structure with low frequency of mutation
- Can transmit information from one generation to another
- Stored information must be decoded and translated into action
- Can duplicate itself with extra fidelity
11
Q
DNA can duplicate itself with extra fidelity, how many identical copies are produced during 1 round of replication that can be distributed during M phase?
A
2 identical copies
12
Q
T or F: Mutation is not inherited and is no a source of variation
A
F: Opposite
13
Q
1830s
Proteins: ___________
Proteios: “______”
A
Proteins: most important molecule
Proteios: “of first importance”
14
Q
1860s F. Miescher
-Isolated molecule from nucleus: _______ while characterizing proteins from ______
A
nuclein
pus cells
15
Q
1866 E. Haeckel
Discovered: most obvious cellular component of the cell is the
A
nucleus
16
Q
1895 E. Wilson
Observed: important nuclear element handed from one cell to another cell is the ________
A
DNA
17
Q
1928 F. Griffith
Conducted _______ experiment using Streptococcus pneumoniae
Two strains: _______ (R) stain and ______ (S) strain
A
transformation
Avirulent (R) stain and Virulent (S) stain
18
Q
In 1928 during the transformation experiment of F. Griffith different set up showed that the _____ stain transformed into the _______ stain which declared the presence of the transforming principle
A
R stain transfromed into the S stai
19
Q
what is transformation?
A
uptake of genetic material from the surroundings
20
Q
Heat kills virulence of S cells. When injected to the mouse, it cause the mouse to become healthy. However, when mixed with living R cells, what occurs which cause the mouse to die?
A
transformation of R cells into S cells
21
Q
1944 O. Avery, C. Macleod, and M. McCarty
identified the transforming principle (TP) as ______
A
DNA
22
Q
1944 O. Avery, C. Macleod, and M. McCarty
When the transforming principle was treated with proteinases and RNAses ______________ retains hence TP is not protein nor RNA
A
transforming ability
23
Q
1944 O. Avery, C. Macleod, and M. McCarty
When TP was treated to remove protein and RNA, the composition of substance left _________________ of ____________
A
matched composition of DNA
24
Q
1952 A. Hershey and M. Chase
Proved: DNA is genetic material of ____________ (phages)
DNA is labeled with P32 while the protein coat is labeled with S35
A
bacterial viruses
25
What is the blender experiment?
Blender separates phages from bacteria after infection
P32 label was present in bacteria after phase infection
-Proves that DNA is injected into cell while protein coat remained outside
26
1952 N. Zinder, J. E. Lederberg
Performed __________ experiment on Salmonella typhimurium
transduction
27
What is transduction?
process wherein bacterial cell can take up DNA through recombination that was introduced by phages
-injection of DNA to the bacterial cell through phages
28
Main contributors of the elucidation of the DNA structure in 1953
F. Crick, J. Watson, R. Franklin, M. Wilkins
29
F. Crick
involved in development of ___________ and ______________
PHD: Xray studies on proteins
radar and magnetic mimes
30
J. Watson
-Child prodigy
-Did labeling of _________
phage DNA
31
M. Wilkins
-Worked on _________ of DNA
Xray diffraction
32
R. Franklin
-Expert on Xray diffraction technique
-Worked on Xray diffarction of DNA
-Captured famous _________ showing xray diffraction - provided essential information for developing a model of DNA
photograph 51
33
who shared the photo 51 and research to Crick and Watson without Franklin Knowing?
Wilkins
34
a process wherein xrays are projected towards a substance and the atoms in the substance would deflect the rays and create an image produced by the DNA molecule
Xray Diffraction
35
1951-1952 R. Franklin, Gosling, & M. Wilkins
-______ DNA structure (orientation)
-Sugar and Phosphate _______ (where)
-Nucleotides ______ (where)
helical
outside
inside
36
1953 J. Watson and F. Crick
________ helix (Single, Double, Triple) - From Pauling
Phosphate in __ (where) Fr
Triple
Center
37
early 1950
L. Pauling
_______ helix DNA (Single, Double, Triple)
Triple
38
J. Griffith
Nucleotides are ______ (shape) and placed _______ of each other
Calculations show possiblity of base pairing between A and T and C and G
Flat; atop
39
E. Chargaff
DNA of all cells contained ____ amounts of A and T and _____ amounts of C and G
equal
40
Chargaff's Rule: Ratio of purine-pyrimidine is ______
evidence for specific pairing
1:1
41
J. Donohue
-________ in the bases can change its position
-Possibility for ________ bonding
H (hydrogen)
Hydrogen
42
DNA
molecular basis of ________-
_______ of all living organisms
double helix structure composed of a __________ backbone and ________ on the inside
heredity
genetic material
sugar-phosphate; base pairs or nitrogenous bases on the inside
43
DNA is a ____________ polymer with deoxyribonucleotides
nucleic acid
44
what are the monomers of DNA or nucleic acid
nucleotides
45
bonds that connect nucleotides
phosphodiester bonds
46
nucleoside is composed of two which are
sugar and nitrogen base
47
what is the sugar of DNA?
2-deoxyribose
48
Purines nitrogen bases
Guanine and Adenine (PUGA)
49
Pyrimidine Nitrogen Bases
Cytosine and Thymine (Not PUGA)
50
A nucleotide contains three which are
Phosphate Group
Sugar
Nitrogen Bases
51
give the negative charge of the DNA
Phosphate Group
52
Important for coiling into condensed structure; component of the DNA
phosphate group
53
what is the charge of histones?
Positive (they are positively charged proteins)
54
proteins that bind to DNA to coil it
histones
55
the sugar molecule, 2-deoxyribose is connected to the SUGAR molecule through a bond called
phosphoester bond
56
the sugar molecule, 2-deoxyribose is connected to the nitrogenous bases through a bond called
Beta-N-glycosidic bond or simply just glycosidic bond
57
difference between the sugar of DNA and RNA
DNA - nucleotide has 2 deoxyribose
RNA - only ribose sugar
58
no. of rings of
purine: ___________
pyrimidine: ________
purine: 1 ring
pyrimidine: 2 rings with the addition of U or Uracil
59
what is the bond between A and T
double bond
60
bond between C and G
triple bond
61
base pairs have similar structures: T or F?
True
62
Alphabet of DNA - our genes are written by alphabet that are represented by the _________ (component of a nucleotide)
nitrogen bases or base pairs
63
bond between sugar and phosphate group and hydroxyl group (C-O-P-O-C)
phosphoester group
64
bond between two nucleotides
phosphodiester bond
65
bond that joins a carbohydrate (sugar) molecule to another group
glycosidic bond
66
components of DNA that is constant in every molecule and found outside
sugar and phosphate group
67
components of the DNA that is not constant in every DNA molecule and found inside
nitrogen bases
68
who developed the Chargaff Rule
Erwin Chargaff
69
Features of the DNA
1. It is composed of ________ polynucleotide stands connected via __________ of bases
2. Sugar:_________
3. Antiparallel - ______, ____
4. Complementary Specific Pairing
A pairs with T and C pairs with G
5. Forms a ______ colil (shape)
1. 2; hydrogen bonding
2. 2 deoxyribose
3. 5'-3', 3'-5'
5. helical
70
1 nm = ___ armstrong
how many nm are there in 78 armstrongs?
7.8
71
Diameter of DNA molecule
2nm or 20 A
72
how many base pairs are there in each turn of DNA
10 base pairs
73
how many nm and armstrong in each turn of DNA
3.4 nm/34A
74
For each base pair in a DNA, how many nm?
0.34nm
75
two DNA strand are held together by
hydrogen bonds
76
sugar phosphate backbone is held together by
phosphodiester bonds
77
base stacking are done through ________
hydrophobic interactions
78
are the nitrogen bases of the DNA polar or nonpolar?
nonpolar
79
base stackings adds _____ to the entire molecule
stability
80
the environment where the DNA can be found is hydrophobic/hydrophilic
hydrophilic
81
direction of the DNA sequence
5' to 3' (parallel)
82
in a DNA carbon 5 has an attachment of _______ and Carbon 3 has _____
Carbon 5: Phosphate
Carbon 3: OH
83
Cells read DNA sequences from ____- to ________
5' to 3'
84
the sequence 5'-TGCA-3' is not the same as5'-ACGT-3' why is this so?
because the base pairs are different
85
Is DNA a static molecule?
No, it is dynamic and change according to the needs of the cells
86
most common conformation of the DNA
B-DNA
-RIGHT HANDED HELIX
87
a type of conformation of DNA that is
right handed but much more compact
11 base pairs per turn
occurs in dehydrating conditions
A-DNA
88
how many base pairs are there in A-DNA?
11 base pairs
89
a type of DNA conformation that is
left handed
unstable experience: from when genes are transcribed and disappears through topoisomerase activity after the gene is no longer transribed
Z-DNA
90
the left part of the DNA is in the _______ to _______ direction
5' to 3' (parallel)
91
the right part of the DNA is in the __________ to _________ direction
3' to 5' (antiparellel)
92
EVIDENCES THAT THE DNA IS THE GENETIC MATERIAL
1. Relative constancy of DNA in all ____ tissues
Starvation = DNA unchanged
2. ____ cells have half amount of DNA in diploid
3. Double of DNA content at ____ phase
4. Cells with extra sets of __l)____ have a propoirtional increase in DNA content
5. Parallelism of ________ absorption with mutation rates
6. ___________ AND _________ in bacteria (two processes discussed before)
7. Production of new ______ particles in bacterial cells
8. RNA content of TMV caused infection and not the ____ (Viruses can either have DNA/RNA as the genetic material)
1. Diploid
2. Haplod
3. S phase
4. chromosomes
5. UV radiation
6. Transformation and Transduction
7. Viral/Virus
8. protein coat
93
what is the difference between Polyploidy and polyteny
Polyploidy - more number of chromosomes
Polyteny - more number of sister chromatids/chromatids
94
All organisms have ____ as genetic material. However some viruses can have _______
DNA;RNA
95
an RNA is composed of ________ polynucleotide strand (number)
1
96
what is the sugar of RNA?
D-Ribose
97
What is the difference between DNA and RNA when it comes to the attachment of oxygen of the ribose?
DNA - no oxygen attached in the deoxyribose
RNA -oxygen attached in the ribose
98
flowchart of process for the DNA replication
2 strands - unwind/separate - base pair - production of 2 identical DNA
99
What is the model of DNA replication?
semiconservative
-each daughter DNA contains one new strand and one old strand from parental template
100
Grew E.coli: nitrogen source consisted of only 15NH4CL.
- 15N-containing cells were transferred to growth media
containing 14N isotopes
- After 1 cell division only one band was observed to
occur between where 15N-DNA and 14N-DNA bands
would normally appear
- RESULT: new DNA was a hybrid molecule containing
15N strand and 14N strand
- After 2 cell division:
- 2 discrete bands: 1 made of 14N- 14N DNA an
Meselson and Stahl Experiment
101
a model of DNA replication where the parental double helix remains INTACT and a second, all new-copy is made
Conservative model (k: INTACT)
102
a model of DNA replication where the two strands of the parental molecule separate and each functions as a TEMPLATE
Semiconservative model (k:TEMPLATE)
103
a model of DNA replication where each strand of both daughter molecules contain a MIXTURE of old and new synthesized parts
dispersive model (k: MIXTURE)
104
initiation starts with_______ (origin of replication)
typically has a lot of ___ pairings
-The are easier to break due to only having ____ h bonds (no.)
-There are multiple origins in the cell happening at the same time
-Formation of ___ stranded DNA templates
orisite
A-T
2
single
105
Proteins or Enzymes in Initation
Helicase
SSBPS (single stranded binding proteins)
DNA gyrase/Topoisomerase
106
an enzyme in initiation which separate 2 strands of DNA
Helicase
107
a protein in iniation which maintains the 2 single stranded templates
-protects it from enzymes like nucleases that breaks phosphodiester bonds
SSBPS(SINGLE STRANDED BINDING PROTEINS)
108
an enyzme in initiation which is needed to relax tension brought by the unbinding of DNA at the fork
nuclease domain: cuts DNA
ligase domain: restitches cut area
DNA gyrase
109
key enzyme for replication
DNA polymerase
110
main enzyme that catalyzes the synthesis of new strands, adds DNA nucleotides to primer
DNA polymerase
111
enzyme that dominantly adds DNA nucleotides to primer
DNA polymerase
112
where are nucleotides added? 5' or 3'
3' end
113
in Elongation and Replication you need a RNA ___ to proceed
primer
114
synthesis of DNA strand is always in the ___ to ____ direction
5' to 3' direction
115
an enzyme that adds RNA primer in elongation
primase
116
direction of the leading strand
3' tp 5' parental strand (antiparallel)
K: 3 LEAD
117
How many primer is needed in the leading strand? since it can synthesize continuously
1 RNA primer only
118
Leading strand
Eukaryotes: 11 +/-1 nucleotides long
Prokaryotes - 10 - 60 nucleotides long
number of nucleotides in leading strand
119
In leading and lagging strand the direction for the following are always:
Proofreading -
Synthesis -
Proofreading: 3' to 5'
Synthesis - 5' to 3'
120
direction of the lagging strand
DNA Pol III: 5' to 3' parental strand direction
121
direction of the lagging strand
DNA Pol III: 5' to 3' parental strand direction
122
lagging strand requires ____ primers (adverb of quantity) since they cannot synthesize continuously
several/many/ a lot
123
Okazaki fragments:
Prokaryotes - approx. 1000 - 2000 nucleotides long
Eukaryotes - approx 100 to 200 nucleotides long
no. of okazaki fragments in lagging strand
K: thousands first 1-2
hundreds 1-2
124
enzymes and proteins in Elongation
DNA polymerase
Primase
DNA Pol I
Ligase
125
enzyme that removes RNA primers and fills gap left by primers since RNA primase cannot stay in DNA molecules
DNA Pol I: K: LEFT BY PRIMERS
126
DNA POL I removes RNA primer in ____ direction exonuclease activty
5'3 direction K: remove and synthesize direction 5' to 3' same lang
127
what is the indicator that replication will now terminate?
-can be initiated by protein for termination or because of structure of replication site
when 2 identical molecules are produced
128
this is released when nucleoside triphosphate binds with OH end, releasing 2 phosphates
Pyrophosphate
129
The simultaneous syntehsis of leading and lagging strands (new model or looping) is catalyzed by the enzyme
replisome
130
replisome is composed of DNA pol III (enzyme) which acts as pairs with 2 catalytic cores: primosome (____ + ____)
helicase + primase (K: HP Laptop)
131
when do telomeres get shorter?
as DNA replicates repeatedly through our lives
132
what END of the DNA is molecule is the longer side 3' or 5'?
3'
133
Telomeres (do/do not) code for RNA genes to prevent gene loss
do not code
134
Upon splitting, DNA polymerase cannot add at the complementary strand with extended and because there is no free ___ end
3' OH end
135
this refer to the maximum amount of times the DNA can replicate before genes can become affected (shortening of telomeres)
Hayflick Limit
136
enyzme that lengthens telomere of linear ends
-complex of proteins and RNA templates
Telomerase
137
telomerase elongate the ____ end used to extend other strand
3' end
138
what is the common telomore end in nucleotides?
TTAGGG PAIRS WITH AAUCCC
139
Significant of Replication
-faithful copying of DNA to produce 2 ___________ molecules
-identical to each other and ___ molecule
-transmit biological information from parent cell to daughter cells (generation to generation)
cell division cannot occur without replication of DNA
2 DNA molecules
parent molecule
140
can cell divison occur without the replication of DNA?
NO
141
Mechanism of High Precision Replication
1. Specificity of base pairing
2. Proof-reading ability of DNA polymerases
3. Excision/Removal repair mechanisms
Mechanism of High Precision Replication
142
enzyme responsible for the repair of thymine dimer (thymine pairs with each other)
-excision and filing
Endonuclease
143
enzyme responsible for the hydrolysis of bond between damaged base and sugar
N glucosidase activity
144
Chromosome Organization
Prokaryotic Chromosome
Double Stranded
approx _____ um long or __ mm
-4x10^6 bp (1kb =1000bp)
-amount of DNA is approx. 1000x the length of E. Coli
11,000 um long or 1.1 mm
145
which is longer in chromosome organization? Prokaryotic or Eukaryotic
Eukaryotic Chromosomes
146
contains the genetic material of prokaryotes
nucleoid
147
how many independent domains are there in the packing of prokaryotes
10 independent domains
148
packing of prokaryotes contains about 10 independent domains
each loop is about ________ bp (40kb) of supercoiled DNA
40,000
149
Packing of Prokaryotes
Histone like protein (protein _)
Protein for DNA packing (Protein _)
Histone like protein - protein Hu
Protein for DNA packing - Protein H
150
how many chromosomes are there in a eukaryotic cell?
46
151
what is the actual DNA LENGTH
6ft (from end to end)
152
how many bp are there in a eukaryotic chromosome?
5500000000 (5.5x10^9)
153
how many cm is 1 chromosome?
7.2 cm (0.01 mm length)
154
Recite or discuss the chromosome packing
Nucleosome formation - DNA + histone proteins
Chromatosome formation - nucleosome + histone octamer
Solenoid Formation - 6 nucleosomes per coil which forms the chromatin thread 30 nm chromatin fiber
Loop formation which is 300 nmn in length
