Lecture 1 Flashcards
(86 cards)
1
Q
Dna polymerase function
A
replicate dna
2
Q
enzymes
A
catalyze rxns
3
Q
hormones
A
regulate
4
Q
rna poymerase function
A
transcription
5
Q
template of transcription
A
mrna
6
Q
trna function
A
transfer aas to ribosome for incorporation into protein. deciphers genetic code found in tmplate
7
Q
rRna function
A
structural component in ribosomes
8
Q
three major forms of rna
A
m t r
9
Q
central dogma
A
dna to rna to proteins
10
Q
retrovirus and central dogma
A
**
11
Q
pathogenic rna viruses
A
polio, measles, sars, influenza
12
Q
rna dependent rna polymerase
A
rna as template to produce more rna (used by pathogenic rna viruses)
13
Q
rna bacteriophages
A
f2, ms2, r17s, qbeta
14
Q
exceptions to central dogma (3)
A
retroviruses, pathogenic rna viruses, bacteriophages
15
Q
bacterial single chromosome structure
A
circular dsDNA
16
Q
plasmids in bacteria produce (3+)
A
inactivation of antibiotics, produce toxins, matabolism
17
Q
ER
A
processs for secretion
18
Q
lysosome function
A
degradation of macromolecuels
19
Q
> 99% of DNA in ?. rest in ?
A
nucleus. mitochondria
20
Q
nuclear dna structure
A
linear ds DNA
21
Q
two types nuc dna
A
genes/related dna and non genes (intergenic)
22
Q
three types of genes
A
single copy (25%), multiple copy (3%), pseudo
23
Q
single copy types
A
exons(1%, info content), intorns (24%, noninformational, have function ie microrna)
24
Q
multiple copy gene types
A
proteins, tRNA coding, rRNA coding
25
pseudogene (two properties)**
nonfunctional (does not produce protein), sequence homology
26
nongenes
non coding dna. helps align chromosmes during mitosis
27
types of nongenes
repetitive dna and noncoding dna
28
lack of telomeres result
fusion, degradation
29
fusion
2 chromosomes side by side, with doublestranded break. dna repair (nat process for recovering ds break), fuses chromosomes
30
degradation
tips unstable. single stranded ends (fray), exonucleases, chew up ss dna regions
31
telomeres
a complex. refers to repetitive dna at tips and proteins that bind the repetitive tips
32
function of telomeres
prevents degradation of tips of dna prone to fray
33
enhance or repress expression by dinding to regulatory genes
*
34
disease associated with repetitive dna (microsatellite dna)
huntington,s fragile x friedrich's ataxia
35
huntingtons
CAG repeat in exon 1 of the hd gene. normal 6-35, abnormal 36-121
36
fragile x *
*
37
methylation of a gc rich region tends to ?
turn off genes
38
approximate protein coding genenes in human
20,000
39
approximate pseuogenes
11,000. evolutionarily deactivated
40
mitochondrial dna codes for ?
2 rnas, 22 trnas , 13 proteins
41
function of mito proteins
7 subunits of nadh-coq reductase, 3 subunits of cyt oxidase, 1 subunit of cyt bc1 complex, 2 subunits af atp synthase
42
uracil is replaced by ? in DNA
thymine
43
know pyrimidine and purine structure
**
44
modification of bases occurs when?
after incorporation into polynucleotide
45
know how modifications of bases effect expression
**
46
lactam vs lactim
*
47
function of double lactam
proper base pairing
48
function of double lactim
*
49
amino vs imino
imino disrupts base pairing
50
results of deprotonation/protonation of bases
disrupts base pairing
51
nucleoside
base + sugar
52
bond between sugar and phosphate
phosphoester
53
know nucleotide and nucleic acid nomenclature
*
54
can only base pair in syn/anti
anti
55
types of single copy genes
exons (mRNA), introns (microRNAs)
56
types of multiple copy genes
mRNA that encodes histones and ribosomal proteins, tRNA, rRNA
57
pseudogene
homology and nofunctionality compared to gene. some error in either transcription, pre-mRNA processing, translation or folding
58
functions of plasmids in bacteria
inactivation of antibiotics, production of toxins, metabolism etc
59
nongenes are either repetitive dna or noncoding dna. what is repetitive dna?
centromeres (location of spindle attachment on chromosome), telomeres (repetitive dna on end of chromosomes), disperesed (repeitive dna)
60
types of repetitive dna
dispersed, terminal, tandem
61
dispersed repetitve dna
copies of transposable elements ( DNA sequence that can change its position within a genome, sometimes creating or reversing mutations). ie microsattelites
62
cause of huntingtons disease
extended CAG repeat in exon 1 of HD genes (35 bad)
63
cause of fragile X (mental retardation 1 gene)
CGG repeat in noncoding region of FMR1 (60 bad)
64
friedreich's ataxia cause
GAA repeat in intron 1 of FXN gene (34 bad)
65
nongenes are either repetitive dna or noncoding dna. what is noncoding dna?
DNA that do not encode protein sequences (some def include rRNA and tRNA) including intergenic (acts to control genes nearby). acts to regulate gene expression and chromosome structure
66
structural of mitochondrial dna
ds circular
67
compartments of mitochondria
intermembrane space and matrix
68
bond between nucleic acids
3-5 phosphodiester bonds
69
whne does z-dna form
when alternating GC base pairs with cytosine methylated
70
keto enol tautomorization of pyrimidines
lactam when no hydroxyl groups formed (only ketones) and dominates at ph &. lactim when 2 ketone is in enol form. double lactim forms at even lower ph.
71
keto enol tautomorization of purines
adenine can form an enol (lactim) at decreased pH. adenine has no keto group.
72
amino-imino tatomerization
amino groups of cytosine, guanine and adenine can form imino groups
73
location of nucleic acid attachments to bases
N9 form purines and N1 for pyrimidines
74
bond between nucleic acid (or nucleoside) and sugar
N-glycosidic between N1 on pyrmimides or N9 on purines and 1 OH of sugar
75
bond between sugar and alpha phosphate
phosphoester from 5 C of sugar
76
dominant forms of ribose and deoxyribose in Rna and Dna
Beta-D-furanose and beta-2'-deoxy-furanose
77
straight chain form of sugars found in solution is a ?
aldehyde
78
puckered ring sugar conformation in B-dna
2'-endo
79
puckered ring conformation in A-DNA and RNA
3' endo
80
dominant conformers of nucleosides (orientation of nucleic acid with respect to sugar)
pyrimidines are always anti (where purine ring is not above ribose). purines are mostly anti.
81
names of ribonucleosides
(deoxy- if dna) adenosine, guanosine, cytidine, thymidine, and uridine.
82
names of ribonucleotides
adenylate, guanylate, cytidylate, thymidylate, uridylate
83
wavelength most commonly used to measure absorption of mixtures of nucleotieds
260nm
84
extinction ceof for ds dna
1/50 ug/ml
85
extinction coef for ss rna or dna
1/40 ug/ml
86
hyperchromic shift (effect)
increase in absorption at 260nm as bases unpair
