Practice Questions Flashcards
(116 cards)
1
Q
Keq negative
A
rxn rate goes forward
2
Q
Keq positive
A
rxn reverse
3
Q
Combustion rxn
A
exothermic
-∆G
+∆S
-∆H
4
Q
ATP is ______ bond
A
phosphoanhydraide bond
5
Q
lipids store more energy than carbs because
A
they have central carbon of lipids own a greater number of valence electrons
6
Q
MMR is clinically related to
A
hereditary non-polyposis colorectal cancer
7
Q
BER is associated with
A
glycolysis
8
Q
Excision endonuclease action
A
cleaves damaged DNA at either side of lesion
9
Q
DNA gyrase function
A
prevents supercoiling of double helix
10
Q
DNA pol III action
A
3’–5’ of template DNA strand
exonuclease proofreading
11
Q
RNA primers are removed by
A
3’–5’ pol I exonuclease
12
Q
craniosynostosis is associated with
A
homeodomain MSX2 (Boston type)
13
Q
Rubenstein-Tayi is associated with
A
haploinsuffieciency of CREB binding protein (CRB)
14
Q
CRB is a
A
HAT
15
Q
NFAT is triggered to ______
A
enter nucleus in the presence of high intracellular Calcium
16
Q
doxorubicin (adriamycin) is a
A
chemo drug that blocks DNA replication in dividing cells by intercalation
17
Q
overabundance of eIF4E cap protein will
A
lead to over expression of proteins coded by mature mRNA
18
Q
3’ AG is bound by
A
U2AF
19
Q
5’GU is bound by
A
U1 snRNA
20
Q
branch a point binds
A
U2 snRNA
21
Q
rifampicin action
A
inhibits transcription of DNA by blocking Pol II at its exit channel
22
Q
scurvy
A
proline
23
Q
western blot uses
A
antibodies as reagent in gel electrophoresis
24
Q
3’ poly A tail is added by 2 successive enzymatic step first is ____
what code?
A
endonucleolytic cleavage of mRNA and polyadenylation of newly generated 3’ OH terminus
endonuclealytic cleavage of RNA occurs at highly conserved sequence
AAUAAA
25
okazaki fragment is initiated by
DNA primase synthesizes a short oligonucleotide that is extended by DNA poly to form okazaki fragment
26
activation domains
some act to recruit co-activators that modify chromatin
others medicate protein-protein interactions needed to recruit general transcription machinery
27
at equilibrium, ∆G =
0
28
Which is not required for DNA replication and RNA transcription
Primers not required for RNA transcription
29
What is required for DNA replication and RNA transcription
RNA
DNA
Proteins
30
5' splice site is recognized by
U1 snRNA
31
ATM protein is involved in
DNA damage check point
32
Next gen enzyme
DNA poly
33
Fidelity of DNA replication at DNA replication fork comes from inherent accuracy of active site of replicative DNA poly to select correct incoming dNTPs. 3'-5' proofreading of DNA poly to exercise incorrect
mismatch DNA repair
34
Many biochemical runs that occur in human cells catalyzed by dehydrogenase enzymes. Change in free energy resulting from rxn depends upon:
1. emf or reduction potential (∆E)
2. relative affinity of electron acceptor for electron donated by electron donor
3. concentration of electron acceptor and electron donor in cell
35
SDS separates based on
size (kd)of protein
36
RNA pol makes
rRNA 18S, 28S, 5.8S
37
swi/snf
ATP hydrolysis allows DNA contacts to be be broken so histone can move along DNA
38
G1 phase
cell divide and growth in g1 phase
39
NER clinical
XP
| Tric
40
BER is initiated by
N-glycosylase
41
PCR temp is
higher than DNA melting temp
42
enzymatic activity XPB is
ATP dependent helices that opens DNA
43
beta amylase is made by
B-secretase followed by Gamma-secretase action of B-amyloid precursor protein
44
TATA box binding protein
helps direct assembly of pre-initiation complex at promotor
45
HR is
dependent on availability of sister chromatid
46
alpha helix and bet sheets are
H bonds
47
DNA poly 3'--5' exonuclease
trans-lesion DNA synthesis repair
48
cyclosporin enzyme activity
peptide prolyl cis- isomerase activity
49
first enzymatic step in cap addition is
triphosphatase
50
mushroom, alpha amatin inhibits
blocks RNA chain elongation by preventing translocation of RNA poly along DNA
51
initial phase translation at 30S subunit attaches to
Shine-Delgarno sequence with 16 S rRNA
52
purpose of NaOH in southern blot
denatures DNA frag in gel so probe can subsequently hybridize to it complementary
53
What leads to double stranded breaks in genome?
1. bleomycin treatment for cancer
2. HIV infection
3. spermatogenesis
4. CT scan
54
What does not lead to double standed DNA break
UV exposure
55
Capping 5' end of newly synthesized mRNA protects 5' end from exonucleolytic degradation
1. during capping guanosine residue is added to 5' end of mRNA backwards
2. capping precedes polyadenylation of 3' end of mRNA
3. e1F4e binds cap, which is critical for translocation of mRNA
56
tamoxifen antagonize estrogen by
binding estrogen receptor and preventing recruit hAT co-factor
57
Alzheimers disease is from a
misfolded protein
58
chloramphenocol and erythromycin target
translation and
| peptiyl transferase
59
PCNA
acts as a clamp which encircles DNA and binds replisome to affect processive synthesis of DNA
60
high energy compounds
1. PEP
2. Phosphocreatine
3. Aceytl Co-A
4. ATP
61
Chromatin
1. contains 4 different histone proteins with hostine complex
2. contains fundamental repreating unit= nucleosome
3. contains linker histone that enables compaction of 10nm fiber to 3nm solenoid
62
post trans mod of proteins
1. methylate lysine
2. acetylation of lysine
3. phosphorthrenonine
4 add sugar to asparagine
63
which domain contains Zn finger structure critical for steroid receptor function
DNA binding domain
64
combinational control
mechanism involving heterodimeriation fo sequence specific DNA binding proteins that greatly increase number of potential DNA sequences to which proteins can bind and thereby allowing small number of transcription facts to regulate large number of genes.
65
how do activator domains function
mediate protein protein interactionsneeded to recruit general transcription machinery
66
how do alkylating agents damage DNA
attack nucleophillic groups on bases, leaving adducts
67
function of helix loop helix, bZIP domains serve in transcription factor to
mediate bidning transcription factor to specific DNA sequence
68
miRNA and siena are
regulatory RNA
69
micheals menton Kcat
number of substrate molecules that are converted to product at saturating substrate concentrations
70
chargoff's rule
B form duplex DNA
71
which DNA repair does MutS and MutL proteins serve?
mismatch repair
72
deoxyadenosine 5'phosphate is a
nucleotide
73
gout
purine
| uric acid
74
lesch nyhan
HPRT1 gene
deficiency of enzyme hypoxanthine
phosphoribisyltransferase 1
high uric acid in body
75
epigenetics
covalent methylation of DNA
76
hypermehtylation
silencing tumor suppressor gene
77
hypomethylation
aberrant transcription oncogenes
78
melanoma
thymine dimer
| UV light
79
AZT and DDL
nucleoside analogue drugs
80
breast/ovarian canver
gene: BRCA1/BRCA2
protein: DSB response
81
bloom syndrome and skin cancer predisposition
protein: DNA helicase
gene: BLM
82
ataxia telangiextasisia and cancer predisposition
gene: ATM
protein: DNA damage checkpoint
83
werner's syndrome
| cancer predisposition
gene: WRN
protein: DNA helicase
3'--5' exonuclease
84
Nijmegan breakage syndrome
gene: NBS1
Protein: DSB repair
85
gene: BRCA1/BRCA2
breast and ovarian cancer
86
gene: BLM
bloom syndrome and skin cancer predisposition
87
gene: ATM
atacia telangiectasis and cancer predispostion
88
gene: WRN
werner's syndrome and cancer predisposition
89
gene: NBS 1
nijmegan breakage syndrome
| cancer predisposition
90
gout caused by
purine, uric acid
91
nonpolyposis colorectal cancer is a problem in
MMR
92
xerdoerma pigmentosum
NER
light sensitivity
abnormal pigmentation
93
cockayne syndrom
NER
94
trichothidystrophy
NER
95
Marfan syndrom
tall and prone to aneurysms
| Mutation of fibrillin gene transcript
96
B-thalassemia
TATA box
97
Gamma-delta-beta thalassemia
deletion in locus control region for the txn of all glob in genes resulting in loss of glob in txn
98
Hemophilia B leyden
promotor or clotting protein gene
99
fragile X syndrome
expansion of CGG count upstream of FMR1 gene
| which causes abnormally high rate of methylation and txn silencing genes
100
craniosynostosis
premature closing of sutures in skull
| homeodomain
101
waardenburg syndrome
white streak in hair
mutation of MIFT
which codes or bHLH
102
androgen insensitivity syndrome
zinc fingers
103
leukemia
HAT or HDAC
104
Rubinstein Taybi syndrom
CREB, CBP (HAT)
105
warfarin
anticlotting drug that targets carboxylation of prothrombin
106
cogenitial disorder of glycosylation (CDG)
dysfunction of glycosylation mechanism results in CDG
107
prion disease
misfolding of proteins
| additional beta pleats
108
alzheimers
AB-42 accumulation
109
parkinsons
beta-synuclein misfiles into lewy bodies
110
alpha amanitin targets
inhibits RNA pol II by binding bridge so it can't translocate
death cap mushrooms
111
rifampicin
binds beta subunit of bacterial RNA poly
| blocks the exit chamber where assembled RNA exits
112
tamoxifen
binds to estrogen receptors as a ligand
| prevents estrogen from binding to active site
113
rapamycin
phosphorylates 4E-BP so that the initiation complex cannot be formed
114
gleevec
cancer treatment competitively inhibits ber-abl kinase
115
antibiotics act to
interferes with ribosome (tRNA binding, elongation and peptidyl transferase)
116
velcade
inhibits proteosome that degrades good proteins resulting in multiple myeloma
