Nucleic Acid Flashcards
(113 cards)
1
Q
The______ involves the transfer of genetic information from DNA to RNA through transcription, and then from RNA to protein through translation.
A
central dogma
2
Q
This flow of information is fundamental to the synthesis of proteins, which are essential for the structure and function of living organISms.
A
Central dogma
3
Q
The central dogma involves the transfer of genetic information from DNA to RNA through_______, and then from RNA to protein through______.
This flow of information is fundamental to the synthesis of proteins, which are essential for the structure and function of living organisms.
A
transcription
translation
4
Q
The genetic material that carries hereditary information in cells.
A
DNA (Deoxyribonucleic Acid)
5
Q
: The process in which information from a DNA sequence is transcribed into RNA. This occurs in the cell nucleus.
A
Transcription
6
Q
The single-stranded nucleic acid molecule that serves as a messenger carrying genetic information from DNA to the site of protein synthesis.
A
RNA (Ribonucleic Acid)
7
Q
The process by which the information in RNA is used to build a protein. It takes place in the ribosomes of the cell.
A
Translation
8
Q
The end product of the central dogma, synthesized through translation.
They play crucial roles in the structure and function of cells, tissues, and organisms.
A
Protein
9
Q
Transcription takes place in….
A
Nucleus
10
Q
Translation takes place in…
A
Ribosomes
11
Q
Nitrogenous bases (2 types)
A
Purines
Pyrimidine
12
Q
Purines
A
Guanine
Adenine
13
Q
Pyrimidines
A
Cytosine
Uracil
Thymine
14
Q
Components of nucleoside
A
Nitrogenous base + Pentose SUGAR
15
Q
Components of nucleotides
A
NucleoSIDE + PhosphaTe
16
Q
Nucleosides are held together by
A
N-glycoSidic bond
17
Q
Nucleotides are held together by
A
Ester bonds
18
Q
phosphate groups are held together by
_________
A
ANHYDRIDE BONDS
19
Q
RIBOSE sugar in RNA
A
D-ribose sugar in RNA
20
Q
DEOXYRIBOSE in DNA
A
2’-deoxy D-Ribose sugar in DNA
21
Q
Building blocks of nucleic acids (DNA/RNA)
A
NUCLEOTIDES
22
Q
Functions of nucleotides
A
• Carriers of activated intermediates
• Structural component of coenzymes
• Second messengers in signal transduction pathways
• Principal biological transducers of free energy
• Regulatory compounds in pathways
• Rate limiting step in glycolysis
• Synthetic analogues as drugs
23
Q
_______smooth pathogenic bacterium causes pneumonia
________rough nonpathogenic mutant bacterium
A
S strain
R strain
24
Q
_______experimental finding: Chargaff’s rule
A
Erwin Chargaff’s
25
Chargaff’s rule
Your purines will always be in equal number with your pyrimidines
1:1 ratio of purines and pyrimidines
26
A-T pair has______ bonds
G-C pair has_______ bonds
2 hydrogen bonds (weaker)
3 hydrogen bonds (stronger)
27
obtained X-ray crystallography images of DNA
Rosalind Franklin
28
created the two-strand, double-helix model
James Watson and Francis Crick
29
STRUCTURE AND PROPERTIES
Made up of nucleotides held together by….
3' to 5' phosphodiester bonds
30
chains
Complementary (5'- 3' -Chargaff's rule)
Antiparallel (3' - 5' the other 5'-3')
31
_____-handed double helix (usually)
Right
32
•_____ base pairs per turn (usually)
10.5
33
Grooves
- backbones are closer together
- backbones are far from each other
Minor grooves
Major grooves
34
Base stacking
2 types of interactions
Hydrophobic interaction
Van der waals forces
35
2 interactions:
__________
• The bases will cluster inside since they are hydrophobic in nature
__________
• These forces help maintain the structural integrity of the DNA double helix by stabilizing the close packing of the bases along the helical axis.
The distance between one atom and another atom
Hydrophobic interactions
van der Waals forces
36
# of base pairs per turn
A-DNA*
B-DNA
Z-DNA**
11
10
12
37
Morphology
A-DNA*
B-DNA
Z-DNA**
Broad and Short
Long and Thin
Long and Thin
38
Screw sense
A-DNA*
B-DNA
Z-DNA**
Right
Right
Left
39
Features
A-DNA*
B-DNA
Z-DNA**
Low humidity/ high salt conditions
Most common
In 5’ end
40
LEVELS OF DNA ORGANIZATION
1.) 2 nm DNA Double Helix
2.) 10 nm chromatin fibril
3.) 30 nm chromatin fibril (Solenoid)
4.) Supercoiled structure
5.) Chromosome
41
First level organization of DNA
2 nm DNA Double Helix
42
Nucleosome level of organization???
2nd level
10 nm chromatin fibril
43
Made of nucleosomes separated by LINKER DNA
DNA wrapped 1.75x over a histone octamer (left-handed)
10 nm chromatin fibril
44
Histone + DNA wrapped around it
Nucleosome
45
30 nm chromatin fibril
Aka
Solenoid
46
When many nucleosome group together in a 30 nm chromatin fibril it is now called a_____
Solenoid
47
Promotes packing DNA into compact structures
To save space it should be tightly packed
Supercoiled structure
48
Condensation of DNA during PROPHASE of mitosis
Chromosome
49
Chromosome
23 pairs of chromosomes (46 total)
22 pairs_____
1 pair of_____
autosomes
sex chromosomes
50
Chromosome
23 pairs of chromosomes (46 total)
22 pairs_____
1 pair of_____
autosomes
sex chromosomes
51
2 types of chromatin
Heterochromatin
Euchromatin
52
Condensed, darker on EM
Sterically ***inaccessible***
Transcriptionally ***INACTIVE***
HETEROCHROMATIN
53
^ METHYLATION; v ACETYLATION
Heterochromatin
54
v METHYLATION;^ACETYLATION
EUCHROMATIN
55
Less condensed, lighter in EM
Sterically accessible
Transcriptionally ACTIVE
EUCHROMATIN
56
RNA
FUNCTIONS depend on the type and can be:
Coding
Non-coding
57
Protein coding RNA
mRNA
58
Non-protein coding RNA
rRNA
tRNA
snRNA
miRNA
IncRNA
siRNA
59
***Most heterogeneous RNA*** (____% of total RNA)
Messenger RNA (mRNA)
5%
60
Conveys information ***from DNA to the translation machinery (ribosomes)***
mRNA
61
***Template for PROTEIN SYNTHESIS***
mRNA
62
mRNA
In eukaryotes, it has a _____at the 5' end and a_____ at the 3' end
methylguanosine cap
poly(A) tail
63
• Primary transcript undergoes splicing prior to protein synthesis
Exons are retained (expressed)
mRNA
64
Most abundant RNA (___% of total RNA)
Ribosomal RNA (rRNA)
80
65
Contributes to the formation and function of ***ribosomes***
Contain ***many*** loops and BASE PAIRING
rRNA
66
rRNA
Molecules differ in their sedimentation coefficients:
→ Prokaryotes:_______ subunits,
made up of 3 types of RNA: 165, 25 and 5S
→ Eukaryotes: ______subunits, made up of 4 types of cytosolic RNA: 18S, 28S, 5S and 5.85
50S and 30S
60S and 40S
67
Smallest RNA (____% of total RNA)
Tiny tRNA
Transfer RNA (tRNA)
15
68
• Adapter molecules that ***translate nucleotide sequences of mRNA into specific amino acids***
• 74 to 95 nucleotides with high % of unusual bases
At least 20 different species
tRNA
69
tRNA
Contains an_____
_____appearance in 2D
anticodon
CLOVERLEAF
70
Functions in ***mRNA processing and rRNA processing***
***Splice together the EXONS*** to form the mature mRNA
Small Nuclear RNA (snRNA)
71
Acts as an interference
Interact with the 3' untranslated region of mRNA to induce mRNA DEGRADATION and TRANSLATIONAL
REPRESSION
Micro-RNA (miRNA)
72
Non-coding transcripts of >200 nt
Long Non-Coding RNA (IncRNA)
73
Involved in regulation of cell differentiation & development, and maintenance of telomere length (TERC and TERRA)
IncRNA
74
_______
Acts as a template for the synthesis of your telomeres
_______
-RNA component of your telomeres
TERC - Telomerase RNA Component
TERRA - Telomeric Repeat-containing RNA
75
Double-stranded RNA (______bp)
***Interfere with the expression of genes*** that have complementary nucleotide sequence to that of siRNA
Silencing RNA (siRNA)
20-24
76
Induces mRNA degradation
siRNA
77
Sugar moiety
DNA
RNA
Deoxyribose
Ribose
78
Purines
DNA
RNA
AG
79
Pyrimidines
DNA
RNA
CT
CU
80
Structure
DNA
RNA
Double stranded
Single stranded
81
Chargaff’s rule
DNA
RNA
Applies
Does not apply
82
Stability
DNA
RNA
Stable
Not stable
83
• Most abundant and functionally diverse molecules in living systems
PROTEINS
84
• Linear polymers of amino acids
Proteins
85
ProteinS
__________(X: variable R group or sidechains)
Linked together by______
N-CX-COOH
PEPTIDE BONDS
86
Side chains
Basic
Acidic
Uncharged polar
Non polar
87
Basic side chains
Lysine
Arginine
Histidine
88
Acidic side chains
Glutamic acid
Aspartic acid
89
Uncharged polar side chains
TTAGS
Threonine
Tyrosine
Asparagine
Glutamine
Serine
90
Non polar side chains
Alanine
Valine
Leucine
Isoleucine
Proline
Phenylalanine
Methionine
Tryptophan
Glycine
Cysteine
91
(9 AAs; Smallest AA)
OXYTOCIN
92
Longest protein is_____ (25,000 AA)
TITIN
93
• Protein sequence can be determined by removing one AA at a time (______)
Edman degradation
94
PROTEIN FUNCTIONS
→ Regulate metabolism
→ Facilitate muscle contraction
→ Provide structural framework
→ Shuttles molecules in the bloodstream
→ Components of the immune system
95
Primary protein structure….
Secondary protein structure_____ bonding of the peptide backbone causes the amino acids to fold into a repeating pattern
Tertiary protein structure three-dimensional folding pattern of a protein due to_____ interactions
Quaternary protein structure protein consisting of more than one…
sequence of a chain of animo acids
hydrogen
side chain
amino acid chain
96
Determined by the AA sequence
Has an N (NH3) and a C (COOH) terminus
PRIMARY STRUCTURE
97
Peptide bonds attach the α–amino group of one to the α–carbonyl group of another
•Partial double-bond character
•Trans-configuration
•Can be disrupted by hydrolysis
Primary structure
98
The folding of short (3-30 residues) segments of polypeptide into geometrically ordered units
Stabilized by______ BONDS
MOTIFS - supersecondary structures produced by packing of side chains from adjacent secondary structural elements
SECONDARY STRUCTURE
HYDROGEN
99
Most common secondary structure
Spiral with polypeptide backbone core and side chains extending OUTWARD
ALPHA HELIX
100
Alpha Helix
~_____ AAs per turn
An example of a 100% a-helix is our _____ and _____
3.6
KERATIN & HEMOGLOBIN
101
AA residues form zigzags or a pleated pattern
BETA SHEET
102
R groups of adjacent residues project in
OPPOSITE directions
Can be parallel or antiparallel
Beta sheet
103
Immunoglobulins are also made up of….
Beta-Sheets
104
Overall 3D shape of the protein
TERTIARY STRUCTURE
105
Tertiary structure
Stabilized by: (5) HDHIV
***Hydrophobic clustering force***
***Disulfide bridges*** (Cysteine)
***Hydrogen bonds*** (between your polar side chains)
***lonic interactions*** (between your charged side chains)
***van der Waals forces*** (to avoid overlapping)
106
assist in protein folding but are NOT the determinants of the final structure;
Hasten the process of the folding before they get degraded
MOLECULAR CHAPERONES
107
• They take those partially folded proteins and hasten the process; they cannot just take proteins that are completely unfolded and then fold them.
Example of a it is Hsp70 helps misfolded proteins fold into the right conformation.
MOLECULAR CHAPERONES
108
2 or more polypeptide chains forming one macromolecule
Not all proteins have a corresponding quaternary structure
QUATERNARY STRUCTURE
109
QUATERNARY STRUCTURE example
Hemoglobin
110
Due to a point mutation (missense) in both genes coding for the ß-chain
• Change from a_______ at position_____
Glu → Val at position 6
Sickle cell
111
Sickle cell
PROCESS:
Polymerization and decreased solubility of the deoxy form of Hb in LOW OXYGEN tension (Low affinity for oxygen) →
Distortion of RBC membrane → Sickling of RBCs (Very Rigid and not flexible) → Occlusion of capillaries
112
Sickle cell
Clinical Manifestations
APT
Anemia
Painful crises
Tissue anoxia
113
Sickle cell
Treatments
Hydration
Analgesics
Antibiotics*
Transfusions
Hydroxyurea
L-glutamine
Crizanlizumab
Voxcelotor
