Molecular Biology Flashcards
1
Q
Molecular basis of biological activity in and
between cells, including molecular synthesis, modification, mechanisms and interactions.
A
Molecular Biology
2
Q
Field of research that started due to the construction of the DNA model.
A
- DNA research
- Genetic engineering
- Gene sequencing
3
Q
Developments
A
- Forensics
- Genetic fingerprinting
- Human genome mapping
4
Q
is the study of the biochemical mechanisms of inheritance.
A
Molecular genetics, or molecular biology
5
Q
Define the terms usually encountered in Molecular Biology
A
It is the study of the biochemical nature of the genetic material and its control of phenotype.
6
Q
Describe the basic parts and the structure of the DNA and DNA
A
It is the study of the connection between genotype and phenotype.
7
Q
is a technique commonly used in laboratories to separate charged molecules like DNA, RNA, and proteins according to their size.
A
Electrophoresis
8
Q
mixture of ________ that we want to _______ and _______
A
- DNA fragments
- seperate
- visualize
9
Q
migration through the pores is called ______
A
sieving
10
Q
_____________ is added that glows in UV light
A
DNA - binding dye
11
Q
we can determine the number of ________ in the DNA molecule based on the ________
A
- base pairs
- distance
12
Q
each band contains thousands of __________
A
Identical DNA molecules
13
Q
_____________ = shorter DNA molecule
A
farther from the well
14
Q
the process of cutting DNA up into smaller fragments using enzymes which only act at a particular genetic sequence.
A
Restriction Digest
15
Q
the process of joining two pieces of DNA together. Ligation is useful when introducing a new piece of DNA into another genome.
A
Ligation
16
Q
a technique used to specifically identify biomolecules following electrophoresis. The
molecule of interest is indicated using either a labeled probe (a complementary strand of nucleic acid) or a labeled antibody raised against a specific protein.
A
Blotting
17
Q
a process used to amplify very small amounts of DNA to amounts which can be used in further experiments.
A
Polymerase Chain Reaction (PCR)
18
Q
we can isolate a specific DNA molecule from the mixture via __________
A
Southern blotting
19
Q
Identify of disease
A
Diagnostic
20
Q
Determine the outcome of a disease
A
Prognostic
21
Q
Determine the possibility of a disease
A
Predictive
22
Q
Determine the response to a treatment
A
Therapeutic
23
Q
A Decade of Discoveries
A
The 1950s
24
Q
Setting the Stage for a Revolution
A
The 1960s
25
Modern Biotechnology is Born
The 1970s
26
A New Research Paradigm and the Commercialization of Biotechnology
The 1980s
27
A Period of Consolidation and Expansion
The 1990s
28
New Challenges, New Technologies
The 21st Century and Beyond
29
Drosophila melanogaster
- fruit fly
- Thomas Hunt Morgan-Columbia University
- Bred cheaply and reproduces quickly
- Confirmed the Chromosomal Theory of Inheritance
30
offspring is from mixture of traits of the parents
17th - 18th century
31
findings on inheritance: Law of inheritance
Gregor Mendel (1856-1863)
32
Each parent contributes a particle or genetic unit to the offspring.
Law of Inheritance
33
1913: ___________ created the first genetic map
- Recombination and Genetic Mapping
- Alfred Sturtevant
34
____________________ - rediscovery, 1900.
- Rediscovering the Mendelian works
- Hugo DeVries, Carl Correns, Erich von Tschermak
35
_________ now accepted based on:
- Nature of chromosome
- Concept of gamete contain only one allele
(i.e: Number of Chromosomes)
Mendelian Law
36
• ___________ - Recombination (Exchange of genetic material either between multiple chromosomes or between different regions of the same chromosome)
Thomas Hunt Morgan
37
• ______ - Chromosomal crossover in Drosophilia melanogaster (1931)
- Curt Stern
38
• ____ - Recombination in mitosis producing mosaics
1936
39
First to produce the genetic map and maize
Barbara McClintock and Harriet Creighton
40
• ____ - Erwin Chargaff produced the first parity rule
- Percentage base pair quality
- %A= %T; %G= %C
- important in the foundation of Watson-Crick Pairs
- The Chargaff's Rules
- 1940s
41
• ____ - Discovered the 2nd parity rule
- %A= %T; %G= %C
1968
42
1869 - _______ isolated "nuclein", DNA with associated proteins from the cell nuclei
- Friedrich Miescher
43
Phoebus Levene
- 1909 - D-Ribose recognition
- 1910 - Tetranucleotide Hypothesis
- 1929 - Deoxyribose discovery
44
• ___________ and ________ proposed the _________ based on studies of ____________ and ______
- 1953 James Dewey Watson( J.D.Watson)
- Francis Harry Compton Crick( F.H.C. Crick)
- double helical model of DNA
- Maurice Wilkins
- Rosalind Franklin
45
discoverd transformation in Diplococcus pneumoniae
1928 F. Griffith
46
demonstrated that bacteriophages are composed of DNA and proteins
1934 M. Schlesinger
47
published the results of biochemical genetics of Neurospora and established One game one enzyme hypothesis
1941 Beadle and Tatum
48
identified that the transforming principle of Diplococcus bacteria was DNA
1944 Avery, Macleod and McCarty
49
demonstrated that in DNA, the number of adenine molecules is equal to thymine and the numbeer of cytosine is equal to guanine
1950 Erwin Chargaff
50
confirmed Watson and Crick's semiconcervative model of DNA replication
1957 Meselson and Stahi
51
isolated DNA Polymerase from E. coli and got Nobel Prize in 1959
1958 Kornberg
52
proposed the "central dogma" of molecular biology
1858 F.H.C. Crick
53
cracked the genetic code present of mRNA
1961 Nirenberg and Matthaei
54
put forward the "Operon concept for regulation of gene expression" and received Nobel Prize in 1965
1961 Jacob and Monod
55
proposed the wobble hypothesis
1965 F.H.C. Crick
56
• Mendel presented his paper
• Known for his pea plant experiments
• Established fundamental laws of heredity or inheritance
1865 Law of Heredity - Gregor Mendel
57
• He isolated genetic material 1869, but the experiment began in 1866.
1866 Purification of DNA – Johann Friedrich Miescher
58
• Introduced the term “molecular disease” in the medical vocabular based on the discovery of the discovery of the single amino acid change in Hgb molecule.
• His findings have set the foundations of molecular diagnostics.
1949 Sickle Cell Anemia Mutation – Linus Pauling
59
1969 - 1970 - Nobel Prize in Physiology or
Medicine was awarded jointly to ________, who predicted the existence of restriction enzymes,
Werner Arber
60
_________, who discovered the first Type II restriction enzyme,
Hamilton Smith
61
________, who demonstrated how to use the restriction enzymes to analyze viral DNA.
Daniel Nathans
62
• Discovered the three-dimensional structure of DNA
• One of the most important biological discoveries in the 20th century.
1953 Structure of DNA - James Watson and Francis Crick
63
important in the production of recombinant molecules. It was discovered and used in the early 1970s.
Rosalind Franklin
64
___________ - most notable product of recombinant DNA technology. It is the first licensed drug using recombinant DNA technology.
- 1970 Recombinant DNA Technology
- Human Insulin
65
important in the production of recombinant molecules. It was discoverd and used in the early 1970s.
Restriction enzymes
66
The _______________ molecules were generated in ______________________________ of Stanford University and University of California San Francisco.
- first recombinant DNA (rDNA)
- 1973 by Paul Berg, Herbert Boyer, Annie Chang, and Stanley Cohen
67
_________________________ comprises
altering genetic material outside an organism to obtain enhanced and desired characteristics in living organisms or as their products. This
technology involves the insertion of DNA
fragments from a variety of sources, having a
desirable gene sequence via appropriate vector
Recombinant DNA technology
68
Cloning of Dolly the Sheep
1996
69
• The Chain Termination Technique
• Paved the way for the analysis of DNA and Restriction Fragment Length Polymorphism
1977 DNA sequencing – Frederick Sanger
70
• Received the Nobel Prize in 1993
• PCR greatly facilitated and revolutionized molecular diagnostics because of its ability to amplify million copies of a target sequence.
• PCR is an exponential amplification technique.
1985 In Vitro Amplification of DNA (PCR) – Kary Mullis
71
• Completed in 2003.
2001 The Human Genome Project
72
• Basic Unit of life
• Discovered by Robert Hooke
• Matthias Schleiden, Theodor Schwann - studied Animal and Plant cells
The Cell
73
The HGP was initiated in 1990 under the
leadership of American geneticist __________, with support from the U.S. Department of Energy and the National Institutes of Health (NIH)
Francis Collins
74
1. All living organisms are composed of one more cells
2. The cell is the basic unit of structure and organization in organisms
3. Cells arise from pre-existing cells
The Cell Theory
75
• 2005 - It is the year when pyrosequencing technology was implemented in an automated system.
• Other notable platforms such as sequencing by ligation (2007), sequencing by synthesis (2011).
2005 - 2011: Sequencing technologies and Genome sequencing
76
• is the fundamental units of genetic information.
• Chemical basis of heredity
• Blueprint of living organisms
• Nuclear DNA = LINEAR
• A Double Helical Structure as proposed
by Watson and Crick (1953)
DEOXYRIBONUCLEIC ACID
77
DNA Replication
- DNA
- DNA
78
Transcription
- DNA
- RNA
79
Translation
- mRNA
- Protein
80
Product of Transcription is RNA, mRNA is the only RNA produced during transcription. You could also produced rRNA and tRNA. But the template for Translation __________
should be mRNA
81
DNA was first recognized and identified by the
Swiss biologist, _____________in 1869 during his research on white blood cells.
Johannes Friedrich Miescher
82
The double helix structure of a DNA molecule
was later discovered through the experimental
data by _________ and _________. Finally, it was proved that DNA is responsible for storing the genetic information of a human being.
James Watson and Francis Crick
83
DNA is great at storing data. 1 gram = _________
700 Terabytes of data
84
DNA from a single cell is ___________
6 feet long if fully stretched out
85
A ____________, ribose or deoxyribose, in a furanose ring form
PENTOSE SUGAR
86
DNA = ________
deoxyribose
87
RNA = ________
ribose
88
______ hold the base on one side and the phosphate on the other side. Thus, sugar hold the components of the nucleotide together
Sugar
89
four nitrogenous bases - _____, _______, ______, and _______.
- adenine
- guanine
- cytosine
- thymine
90
Purines - double rings
- Guanine
- Adenine
91
Pyrimidines - single rings
- Cytosine
- Thymine
92
on the outside of the double helix. Two hydroxyl groups of each phosphate are involved in phosphodiester bonds. The third is free and dissociates its proton at physiologic pH, giving the molecule a negative charge.
Phospate group
93
have a single six-membered ring
Pyrimidines (cytosine, thymine, and uracil)
94
have a six- membered ring fused to a five-membered ring
Purines (adenine and guanine)
95
In DNA, the sugar is ________; in RNA, the sugar is ________.
- deoxyribose
- ribose
96
REVIEW (COMPLEMENTARY BASE PAIRS – Watson-Crick Base Pairs):
- Adenine – Thymine
- Cystosine - Guanine
97
inked together by _________ between the 3’ hydroxyl on the sugar of one nucleotide and the 5- phosphate on the sugar of another nucleotide.
phosphodiester bonds
98
The linkage between the sugar and the base is called the ___________.
GLYCOSIDIC BOND
99
● Erwin Chargaff, a biochemist, discovered that the number of nitrogenous bases in the DNA was present in equal quantities. The amount of A is equal to T, whereas the amount of C is equal to G. A=T; C=G
● In other words, the DNA of any cell from any
organism should have a 1:1 ratio of purine and
pyrimidine bases.
Adenine (A) pairs with Thymine (T) by 2 hydrogen bondsGuanine (G) pairs with Cytosine (C) by 3 hydrogen bonds
Chargaff's Rule
100
• As describe by ________ and ______.
Mr. Watson and Crick
101
DNA is composed of two polynucleotides, anti-parallel with each other (One strand runs from 5' to 3', while the other strand runs from 3' to 5') = ___________
Opposite Direction
102
On the outside
Sugar-Phosphate Backbone
103
On the inside
Hydrophobic Bases
104
The two strands are connected by ___________ between base pairs (Watson-Crick Base Pairs):
Hydrogen Bonding
105
Adenine - Thymine
2 Hydrogen Bonds (Easier to separate)
106
Cytosine - Guanine
3 Hydrogen Bonds (Harder to separate)
107
3 Steps performed in several cycles
1. Denaturation of the DNA
2. Primer Annealing
3. Primer Extension by DNA Polymerase
108
Objective is to separate the double stranded
DNA into separate single strands via
denaturation through application of ____.
Heat
109
When we increase the temperature (________) the two DNA strands will be separated (in the living cell this is done via helicase enzyme). Hydrogen bonds between the 2 strands of DNA are broken.
around 95 C
110
What is the significance of the MAJOR and MINOR GROOVE?
Based on their analysis, it is the site where the transcription factors interact.
111
• Synthetic primers (preformed and are not
produced by primase) bind to the regions that youwish to amplify.
• Temperature is lower (_________)
about 40 to 60oC
112
• Your primers will be extended by the DNA Polymerase synthesizing your desired DNA sequence
• Carried out at ______. DNA polymerase from Thermusaquaticus (_____________) is used because it can withstand high temperatures.
- 72oC
- Taq DNA polymerase
113
a. The mitochondrial genome is a double-stranded circular DNA molecule found within the mitochondrial matrix.
b. The genetic code for the mitochondria is slightly different than that of genomic DNA.
c. The genome codes for 13 protein subunits of the electron transport chain, a large and small ribosomal RNA (rRNA), and 22 transfer RNAs (tRNAs).
Mitochondrial DNA
114
a. The entire chromosome of the bacterium
Escherichia coli is circular and contains more
than 43, 106 base pairs.
b. The DNA molecule in the longest human
chromosome is linear and is over 7.2 cm long.
DNA molecules are extremely large
115
Most DNA is located in the cell nucleus (where it is called ________), but a small amount of DNA can also be found in the mitochondria (where it is called _________________).
- nuclear DNA
- mitochondrial DNA or mtDNA
116
considerably smaller than DNA
Size
117
contain ribose sugar (instead of deoxyribose)
Sugar
118
contain uracil (instead of thymine)
Nucleotide
119
usually exists in singel-strand form
Form
120
tRNA
- >50
- 74 - 95
- 10-20%
- Long
- Translation
121
rRNA
- 4
- 120 - 5000
- 80%
- Long
- Translation
122
Type
- Species per cell
- Length (b)
- Proportion
- Lifespan
- Function
123
mRNA
- > 1000
- 400 - 600
- 5%
- Short
- Translation
124
snRNA
- ~10
- 100 - 300
- <1%
- Long
- Splicing
125
- double helical regions assume conformations resembling A-DNA
- antiparallel
A-Form Helix
126
show A-form conformations
DNA-RNA Hybrids
127
initially synthesized as single-stranded polymer by the process of transcription
RNA
128
linked into a polar molecule by phosphodiester bonds
Ribonucleotides
129
Roles of Some RNAs
-structural
- interact extensively with specific proteins
- catalytic functions → form some very
complex structures
130
RNA is a single-stranded but can form regions of double helix by folding back on itself
Double-Stranded RNA
131
Reguires 2 Hydrogen Bonds
Adenine with Uridine
132
Requires 3 Hydrogen Bonds
Guanine with Cytosine
133
contains helices, hairpin loops,
internal loops, and bulges
5S Ribosomal RNA (rRNA)
134
base pairing and extensive stacking
interactions → compact shape
Transfer RNA (tRNA)
135
not all portions code for polypeptides
Basic Features
136
carry information for the production of multiple polypeptides
Polycistronic
137
sequences that code for proteins
Cistrons
138
contain sequences that are never translated into protein
Leader Sequence/5’-Untranslated Region (5’-ULR)
139
contain sequences that are never translated into protein
Trailer Sequence/3’-Untranslated Region (3’-UTR)
140
sequences between cistrons
Intercistronic Regions / Spacers
141
Multiple translation start sites
Prokaryotic mRNA
142
Single translation start site
Eukaryotic mRNA
143
- Most heterogeneous type in terms of:
• size (500-6000 nucleotides)
• base sequence
- carries genetic information from DNA →
cytosol → ribosomes → template for protein
synthesis
Messenger RNA (mRNA)
144
● Basic Feature:
○ Monocistronic- carries the information from single polypeptide
○ Precursor: ________________ (hnRNA)
○ Leader Sequence (5ULR)
○ Trailer sequence (3UTR)
○ Poly A Tail- 200-300 bp on the _____ end of RNA
○ Cap- _____________ end of Eukaryotic mRNA
• Consist of 7 Methylguanylate molecule
EUKARYOTIC MRNA
145
found in association with different proteins as
components of the ribosomes (site of protein
synthesis)
Ribosomal RNA (rRNA)
146
1. ________
Structural
147
catalytic for some of the translation reactions
Ribozyme
148
3. ___________
80% of Ribosomal mass
149
smallest (4S)
Transfer RNA (tRNA)
150
serve as __________ → carry specific amino acid (covalently attached to its 3’-
end) to the site of protein synthesis → _________________ into newly synthesized proteins in a templatedependent manner
- adaptor molecule
- facilitates incorporation of amino acids
151
- Prokaryotic rRNA
a. Basic Features and 3 types:
- 23S rRNA- 2904 nucleotides
- 16S rRNA- 1541 nucleotides
- 5S Rrna- 120 nucleotides
152
- Eukaryotic rRNA
- Basic Features
- 28S rRNA- 4718 nucleotides
- 18S rRNA- 1874 nucleotides
- 5.8S rRNA- 160 nucleotides
- 5s rRNA- 120nnucleotides
153
- Prokaryotic tRNA
a. Basic Features
unique structural features necessary for
recognition by the enzyme that catalyze
amino acid attachment to tRNAs
154
- Eukaryotic tRNA
a. Basic Features
- similar to prokaryotes in: size and structural
features
- heavily modified post transcriptionally
155
EUKARYOTIC SMALL RNAs
A. Small Cytoplasmic RNAs (scRNAs)
- 7s RNA
- 294 nucleotides
- Used as a component for signal recognition
particles
156
B. Small Nuclear RNAs (snRNAs)
- Small nuclear ribonucleoprotein
particles(snRNPs)
- Function: ___________hnRNA mRNA
157
Serves as defense system of eukaryotic cell; used in laboratory to “knock out” a gene being studied
• Defense system: In the event that a cancer gene is introduced, the siRNA will interfere with the translation process, in order to prevent
further spread or multiplication of the cancer gene.
Small Interfering RNA siRNA
158
Inhibits translation, affecting gene expression and cell development
Micro RNA miRNA
