Week 5 Flashcards Preview

B1 > Week 5 > Flashcards

Flashcards in Week 5 Deck (211)
1

Pyrimidine pathway begins with what?

glutamine, CO2, 2 ATP

2

Describe what occurs in Complex III

contains cavern, electrons picked up by cytochrome C and taken to IV, pumps 4 protons to intermembrane space

3

Cytochromes contain _____ cofactors that can be reduced or oxidized

heme

4

How is the X chromosome inactivated?

packaged into transcriptionally inactive heterochromatin. Heterochromatin coats inactive X DNA and prevents its transcriptional expression --> forms Barr body. Xist gene encodes RNA responsible for mediating this silencing.

5

When non-equal concentrations are known, which equation should be used for delta G?

Delta G = Delta G naught + RTln[y]/[x]

6

Purine biosynthesis starts with what molecule?

ribose-5-P

7

Describe the enrgy required to convert oxaloacetate to citrate

-9 kcal/mol

8

In sperm, all imprints are erased and rewritten with _______ pattern; in eggs, rewritten with _______ pattern; even in genes that come from opposite sex parent

paternal, maternal

9

Describe how acetylcholine promotes the synthesis of NO

Acetylcholine binds to GPCR on endothelial cell --> IP3 generated --> increases Ca++ --> activates NO synthase --> NO produced from arginine

10

Isocitrate to alpha-ketoglutarate to succinyl coA - both steps are promoted by this cofactor

Calcium

11

What is the wobble base on tRNA?

3rd position in codon not totally required to match by all tRNAs (sometimes you get an I matching)

12

In Huntington's Disease, there is greater expansion in _______ parent transmission than in ______

male, female (gametogenesis)

13

_________ genes are susceptibility targets for numerous human pathologies such as Angelman and Prader WIlli Syndrome

imprinted genes

14

A positive feedback mechanism that results in ______________ would be an NZ that is activated by a signaling molecule but is then further stimulated by products that bind back to the NZ/signal complex and further stimulate it.

switchlike behavior

15

Nucleoside monophosphate kinases convert ATP and NDP to

ADP and NDP

16

What are the three tissues most dependent on oxidative phosphorylation?

heart, skeletal muscle, central nervous system

17

TCA cycle enzymes are found in what part of the mitochondria?

Matrix

18

Describe how the COX2 pathway can result in neoplasia (4 factors)

promotes tumor angiogenesis, induces tumor cell growth, inhibits apoptosis, dec immunosurveillance

19

Describe the four step process of tRNA binding

1) aminoacyl tRNA binds to vacant "A" site
2) a new peptide bond is formed at "P" site
3) mRNA moves 3 nucleotide positions through ribosomal subunit to E site
4) spent tRNA is ejected and the ribosome is reset

20

When a hormone secreted from a cell travels through the blood stream and binds to receptor on target cell, what signaling system is occurring? (encounter lots of cells during travel)

endocrine

21

Describe the age and conflict of the child in the oral stage.

birth-1 yr, primary conflict - weaning, fixation can lead to excess reliance and vulnerability to overconsumption of food or alcohol. Frustrations can lead to pessimism, envy and aggression.

22

__________ is usually the first AUG from 5' cap site

kozak sequence

23

During pyrimidine synthesis, _____ is added halfway through the cycle to produce orotidine (OMP)

PRPP, catalyzed by orotic acid transferase

24

DNA methyltransferases can be indirectly repressed by _________

mir-29b

25

Modified ________ ensure that a differentiated cell stays differentiated

histones

26

Describe how NO causes rapid relaxation of smooth muscle cell

NO binds to guanylyl cyclase and converts GTP to cyclic GMP which causes rapid relaxation

27

How do ROCK and PKC activation inhibit MLCP activity?

ROCK phosphorylates MYPt1 inhibitory protein and PKC phosphorylates CPI-17 inhibitory protein, which leads to inactivation of MLCP

28

How do macrolides (such as erythromycin) inhibit protein synthesis?

prevent the Movement of ribosomes(translocation)

29

Non-specific NSAIDS also block the inducible COX2 pathway. Normally, the COX2 pathway can lead to ________ and _______ via PGE2. Why are these dangerous?

inflammation, neoplasia
causes ulcers

30

How is phosphate transported to the matrix to provide substrate for ATP synthase?

Through the phosphate translocase (symporter), moves protons and phosphate in

31

In Fragile X, there is ____% penetrance in females with one full mutation and ____% penetrance in males with one full mutation

50%, 100%

32

In addition to thymine degradation, B12 plays an important part in conversion of __________ to methionine (catalyzed by methione synthase)

homocysteine

33

In a group of identical signaling cells, each cell receives a strong ________ signal . (also affects cells in the immediate enviro of the signaling cells)

autocrine

34

In the cytosine uracil degradation pathway, what are the compounds eventually degraded to?

acetyl SCoa

35

Describe miRNA therapy in asthma

decreases immune response

36

Progressive loss of motor control and psychiatric problems including dementia and affective disorder characterize this repeat expansion disorder that usually presents between ages 30 and 50

Huntington's Disease

37

Describe initiative vs guilt stage of Erikson

3-5 years, corresponds with phallic stage, interpersonal skills develop, too much control will lead to sense of guilt and inhibition and tendency to follow

38

Describe the attachment theory

emotional and physical attachment gives greater sense of stability in infants and toddlers, however if primary caretakers are overly anxious and depressed can have profound effect on kids

39

Pyrimidine pathway is activated by _____ and ATP

PRPP

40

Name 5 mechanisms of desensitization or negative feedback

- receptor sequestration (receptor returned to membrane, LDL is an example)
- receptor down regulation (receptor degraded, EGF receptor)
- inactivation of signaling protein (phosphorylation)
- receptor inactivation (examp GRK)
- production of inhibitory protein (examp arrestin)

41

Name two compounds that act in an autocrine manner (FADs of arachadonic acid)

eicosanoids
prostaglandins

42

_________ both inhibit electron transport by inhibiting cytochrome oxidase

cyanide, carbon monoxide

43

The nitrogens in purine biosynthesis come from which compounds

Aspartate, Glycine, Amide N of glutamine

44

What happens in folic acid deficiency?

Cannot synthesize THF, slows down step in purine synthesis process

45

How does ChloramPhenicol inhibit protein synthesis?

inhibits Peptide bond formation (via peptidyl transferases)

46

True or false: A decreased delta G for a reaction makes the reaction proceed faster

FALSE

47

The most common form of inherited neurodevelopmental disorder is _________

Fragile X

48

In thymine degradation, ____ is required to break down methyl malonyl semialdehyde (MMSA) to succinyl sCoA [last step]

B12

49

In an abrupt response, as the number of activator molecules that must be bound simultaneously to effector proteins to activate them increases, the slope of the activation curve _____ as does the ________________

activation curve, response start time

50

Describe the limiting step in the Krebs Cycle

Oxaloacetate levels

51

Describe what occurs in complex IV

Contains 3 subunits. Subunit I contains two heme groups and a Cu. Subunit II contains two Cu ions. Electrons get picked up by Cu on subunit II and travel through Subunit I which causes 2 protons to get pumped through

52

The mRNA transcript associates with ______ at 5' cap and 3' poly A tail then mRNA positioned in the small ribosomal subunit

eukaryotic initiation factors (eif-2 important)

53

______ inhibits ATP synthase by inhibiting Fo subunit

oligomycin

54

True or false: Delta G naught depends on substrate and production reactions

FALSE DELTA G. Delta G naught is a CONSTANT

55

What three inputs turn Cak Kinase activity on?

phosphate removed from specific region, phosphate added to another specific region, cyclin is present

56

SSRI's are prescribed to treat anxiety disorders, OCD, premature ejaculation, eating disorders and sometimes _____

IBS

57

During _________, each cell contains a population of different mitochondria that are randomly distributed throughout the cell. When the daughter cells form, they randomly inherit a variable number of mitochondria.

mitotic segregation

58

GTP-binding proteins are in active state when _____ is bound and inactive when _____ is bound

GTP, GDP

59

Tetracyclines (TTC) inhibit protein synthesis by ____

TRNA Tries but Can't (prevents aminoacyl tRNA from attaching to A site of ribosomes)

60

Mitochondrial disorders normally manifest as what three types of disorders?

myopathies, neuropathies, encephalopathies (also linked to DM)

61

________ both prevent electron transfer from FE-S center to ubiquinone

Rotenone, Arigtal

62

Name 4 clinical consequences of B12 deficiency

1) pernicious anemia
2) megaloblastic anemia
3) neuro dysfunction
4) folate deficiency

63

Describe the steps of the Krebs cycle and where energy is produced.

Acetyl CoA enters the Krebs cycle.
Citrate --> IsoCitrate --> Alpha-Ketoglutarate --> Succinyl-Coa --> Succinate --> Fumarate --> Malate --> Oxaloacetate. Isocitrate, Alpha-Ketoglutarate, and Malate conversions yield NADH. Succinyl Coa to Succinate yields GTP. Succinate --> Fumarate yields FADH2.

64

In _______ signaling, a signaling cell releases local mediator to nearby target cells (affects only cells in immediate environment of signaling cell)

paracrine

65

In valine, isoleucine and threonine degradation, B12 is required for conversion of which compound to succinyl CoA?

methylmalonyl-CoA (catalyzed by methylmalonyl CoA mutase)

66

What drug inhibits DHFR and stops cancer cells from synthesizing nucleotides?

Methotrexate

67

How does clindamycin inhibit protein synthesis?

makes ribosomes Cling to mRNA (prevents translocation)

68

_____ and ____ are two flavoproteins that tightly associated with proteins and can accept one or two electrons

FADH2 and FMNH2

69

Describe the age and conflict of child in latency.

6-puberty. Ego and super ego develop and sexual impulses are repressed. Struggles can cause impairment in social skills and self confidence

70

Although SSRIs are just as effective as anticyclic antidepressants, what is a benefit of using them?

much higher toxic dose and fewer or milder side effects

71

When protons are pumped across membrane it creates a proton gradient, a charge gradient, and through mass action a __________ which drives ATP synthesis

proton motive force

72

Describe the energy required to convert malate to oxaloacetate in the Krebs cycle and how this moves forward

+7 kcal/mol, high malate concentrations

73

MELAS, mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes, sometimes only manifests as ____

DM

74

Describe the age and conflict of the child in anal stage.

1-3 years, conflict over toilet training, leads to anal retentive (too strict of parents) or repulsive personalities (too lenient)

75

Where do the nitrogens come from in pyrimidines?

glutamine, ribose-5-phosphate (comes from aspartic acid)

76

How is ATP transferred to the intermembrane space (and eventually cytosol)?

Through adenine nucleotide translocase (antiporter, ATP out of matrix, ADP into matrix)

77

In pyrimidine synthesis, what is required?

UMP

78

True or false: even normal alleles change every generation

TRUE - alleles are unstable af

79

Describe the effect of mi26 on liver cancer in rats

suppressed tumorigenesis

80

Stored nutrients and ingested foods get converted into energy sources via _________ reactions then _________ reactions reactions take that energy and use it to do osmotic work, mechanical work, and other cell work

catabolic, anabolic

81

Regulation of histone modification and heterochromatin formation, DNA methylation, Genomic imprinting, gene silencing and X chromosome inactivation are all examples of _____________

epigenetic processes

82

Conversion of energy from NADH to ATP is about 40% efficiency. Combined reaction free energy has -33 kcal/mol which generates ___ ATP

3

83

The carbons in purine biosynthesis come from which compounds

THF, glycine

84

What types of mutations would resemble mitochondrial disorders?

mutations in nuclear genes responsible for either Ox-phos components or for mitochondrial regulation

85

If enthalpy is greater than 0, reaction can still be spontaneous even if entropy is ______

greater than 0

86

Huntington disease results from repeat expansion that creates a _____________ mutation

gain of function

87

Probenecid inhibits uric acid ______ while colchine is an inflammatory drug, both used to treat gout

excretion

88

Describe the salvage pathway, also known as the degradation pathway of nucleotides.

Begins with RNA & DNA --> nuclease NZ breaks down to nucleotides --> phosphatase breaks down to nucleosides --> nucleosides undergo phosphorylation rxns --> bases --> PRPP added via enzyme --> NMP

89

Describe the function of Prozac and Lexapro that allow them to be SSRI

Block the reuptake transporters located on the membrane of the transmitting neuron (at synaptic cleft)

90

In repeat expansion disorders, congenital form is seen only in infants of affected _________

mothers

91

Describe the mechanism of how insulin receptor (RTK) activates Ras protein

It phosphorylates itself once activated, then these phosphorylated tryrosines recruit IRS1 via a PTB domain. IRS1 phosphorylated on tyrosines, which binds SH2 domain on Frb2. Fb2 binds Sos and Sos acts as GEF to activate Ras. Other phosphorylated tyrosines on IRS1 recruit add'l signaling protein that have SH2 domains.

92

Describe miRNA mediated gene silencing

Drosha is a dsRNAse that will breakdown pri-miRNA to precursor miRNA. After GTP-dependent export from nucleus, dicer chops miRNA. miRNA then bound to RISC with Argonaut 2. RISC guided to target DNA and degrades if perfect complimentary

93

In myotonic dystrophy, a man who is a premutation carrier for a repeat expansion disorder has a ____ risk of having a severely affected child. This man's daughters would have a ___ risk of having a severely affected child.

low, variable but could be high

94

____________ inhibits thymidylate synthase

5-fluorouracil

95

What is required to make purines?

IMP

96

True or false: Each individual has same two alleles in all somatic cells but during gametogenesis, each allele varies in every gamete

TRUE

97

In mitochondrial disorders, affected females transmit disease to _____ of their children whereas males transmit disease to ____.

all, none

98

Adenylosuccinate lyase is involved with converting aspartate to __________

fumarate

99

Cortisol, thyroxine, estradiol, testosterone, vitamin d3 and retinoic acid all are _____________

steroid hormones

100

____________________ associates with 5' cap of mRNA and then shorterns the poly A tail in the 3' to 5' direction

deadenylation nuclease (DAN)

101

Describe the FMR related disorders

FXTAS - fragile X associated tremor/ataxia syndrome (late onset), males (and some females) with FMR1 premutation
FMR1-related POI - ovarian insufficiency, 20% of females with FMR1 premutation

102

Molecular switches fall into two categories. In both categories what determines whether protein is inactive or active? What are two classes?

gain or loss of phosphate groups
two classes are inactivated/activated by phosphorylation and GTP-binding proteins

103

Why can't thermogenin be used for weight loss?

Great way to burn energy but energy needs somewhere to go so converts to heat and temperature gets very elevated

104

How are signaling systems defined? (3 characteristics)

distances over which they operate, effective concentration of signaling molecule req to elicit a response and affinity of receptor for its ligand

105

Myotonic dystrophy results from a repeat expansion in _____________ RNA that decreases RNA stability (3' untranslated region)

protein kinase

106

What is the equation that relates delta G, H, and S

Delta G = Delta H - T* Delta S

107

What is the key regulatory step in pyrimidine synthesis catalyzed by?

aspartate transcarbamyolase

108

_________ play an important role in pain, fever and inflammation and thus the synthetic pathways for these compounds play an important role in pain

eicosanoids

109

NSAIDs such as ASA and ibuprofen block the first _________ step in catalyzed by _______ and ________ and thus inhibit prostaglandin, prostacycline and thromboxane synthesis

oxidation, COX1 and COX2

110

Folate derivatives, THF, are carbon carriers involved in what two things?

amino acid metabolism and nucleotide synthesis

111

Protons go around F0 subunit which causes the stalk to turn and conformational changes of alpha beta subunits in F1. This allows ADP and phosphate to bind in one conformation, then when the stalk turns what happens?

ATP is synthesized and kicked out

112

On what part of tRNA does amino acid bind

3' end, CCA tail

113

_____ can target heart disease at many different places

miR21

114

In endocrine signaling, hormones are greatly diluted in the blood stream so receptors are _________ whereas in synaptic signaling, neurotransmitters are released into the synapse which is only 100 nm wide and receptors are _______

high affinity, low affinity

115

In _________ signaling, a membrane bound signal molecule on the signaling cell makes contact with the target cell

contact-dependent

116

Folate deficiency decreases purine and dTMP synthesis while arrests cycle in the ________ and results in ___________________

S-phase, megaloblastic anemia

117

In MERFF (myoclonic epilepsy with ragged red fibers), heteroplasmy is seen. Describe heteroplasmy.

Mosacisim caused by variable number of mutant mitochondria per cell

118

Describe the industry vs inferiority stage of Erikson

5-12 years, corresponds with latency, peers and teachers become more important, self-explanatory

119

Ick, PI3K, PLC-gamma, IP3, Ca++, Src , JAK-STATs and NF-KB all fall under what class of receptors?

NZ linked

120

_________ leads to impaired dTMP synthesis, megaloblastic anemia, hyperhomocystenemia with increase risk for CVD, and neutral tube defects in pregnancy

Folate deficiency

121

The ________ is method by which NADH moves from cytosol into mitochondrial matrix in the liver, kidney and heart

malate-aspartate shuttle (oxaloacetate to malate occurs in cytosol producing NAD+ then reversal of reaction occurs in matrix producing NADH)

122

Arachadonic acid yields ______ and ______

COX1 and COX2

123

________ acts as an energy shuttle for phosphorylation of ADP --> ATP

creatine phosphate

124

What activates purine biosynthesis? How many ATPs are used?

presence of PRPP, 2 ATPs used to begin and then 3 more used later (total 5)

125

True or false: Mitochondria disorders are often progressive or do not manifest until adulthood because function is sufficient at birth but then deteriorates with age and accumulation of add'l mutations

TRUE

126

Where do the carbons come from in pyrimidines?

aspartate, CO2

127

Angelman Syndrome and Prader-Willi both the same loci on which chromosome?

chormosome 15 - q arm of 13th loci

128

True or False: Heme B contained within complex II plays a vital role in electron transport chain

FALSE, NOT INVOLVED

129

When delta H is less than 0, reaction is ______ whereas when delta H is greater than 0, reaction is ______

exothermic, endothermic

130

Describe the age and conflict of the child in phallic stage.

3-6 years old, primary conflict - Oedipal. Fixation leads to self-centered and narcissistic personality, commitment issues. Freud thought that this may cause homosexuality.

131

Name 5 factors that can induce the COX2 pathway

mitogens, growth factors, oncogenes, carcinogens, cytokines

132

What activates deoxy synthesis?

ATP presence

133

Describe the irreversible steps in the Krebs cycle

Alpha-ketoglutarate to succinyl-Coa, and oxaloacetate to citrate

134

Protein phosphatase _________ while protein kinase __________

dephosphorylates, phosphorylates

135

Huntington's Disease is a ______ penetrant _____ disease: normally results in death within 15 years of diagnosis

100%, protracted disease

136

Describe the generativity vs stagnation stage of Erikson

40-65 years, "big picture" and our place in it, giving back to society, failure would lead to feeling stuck, midlife crisis

137

What is delta G naught equal to at equilibrium (Delta G equal 0)

-RT*ln*Keq or -RT*ln[y]/ln[x] @ equilibrium

138

How do aminoglycosides (streptomycin) inhibit protein synthesiS?

A is first letter, thus aminoglycosides inhibit initiation (first step of translation) by preventing formation of initiation complex

139

Describe the autonomy vs shame and doubt stage of Erikson

18m-3 years, corresponds with anal stage, toilet training, this is where children develop independence

140

Describe sx of Angelman syndrome

speech difficulties, speech problems, seizures, jerky movements, and an unusually happy disposition

141

Nucleotide diphosphate kinases convert ATP and NDP unto

ADP and NTP

142

Describe equation for delta G including Reduction potential (deltaE)

Delta G = -nF*deltaE; n is number of e-s transferred, F is Faraday's constant

143

The ___________ synthesis pathway is targeted by several different cancer drugs, involves dUMP

thymidylate

144

The ________ is method by which NADH from cytosol gets into the mitochondria matrix in the skeletal muscle and brain

Glycerol-3-phosphate shuttle

145

What causes Angelman Syndrome?

individuals missing gene activity that normally comes from mom - mom's copy either defective or missing OR there are two paternal copies

146

In myotonic dystrophy, when does expansion occur and in which sex?

gametogenesis in females

147

Thermogenin is found in brown fat. What is its action?

It uncouples phosphorylation from electron transfer (ox phosphorylation)

148

Under chromatin remodeling, miRNAs can affect positioning of ________ by promoters

nucleosomes

149

What do patients with pyruvate dehydrogenase deficiency exhibit?

High serum levels of lactate --> acidotic

150

Describe acetylcholine's action on
a) heart pacemaker
b) salivary gland
c) skeletal muscle cell

a) decreased rate of firing (GPCR)
b) inc secretion (GPCR)
c) contraction (ion channel)

151

Elongation factors help enhance translation and control accuracy by _________

proofreading, incorrectly based paired tRNA preferentially dissociate

152

Adenylate kinase converts ATP and AMP into

2 ADP

153

When delta G is less than 0, reaction is ______ whereas when delta G is greater than 0, reaction is ______

exergonic, endergonic

154

Describe identity vs role confusion stage of Erikson

12-18 years, struggle to find place and identity, failure may lead to experimentation

155

Fragile X mental retardation results from an expansion on FMR1 ____________ (5' untranslated region) which inhibits transcription due to hypermethylation

RNA binding protein

156

Allopurinol inhibits uric acid formation by inhibiting the enzyme that forms it ___________

xanthine oxidase

157

What are the four "canonical" features of MERFF?

myoclonus, generalized epilepsy, ataxia, ragged-red-fibers in muscle biopsy

158

In ATP Synthase, ___ is a transmembrane protein and ___ contains a stalk that turns

F0, F1

159

Skeletal muscle deterioration (starting with the face), cardiac and smooth muscle defects, an inability to relax muscles, cataracts and mild mental retardation are all seen in _______________. (Which are "subclinical?")

myotonic dystrophy, cataracts and abnormal electromyogram

160

Describe the ego integrity vs despair stage of Erikson

65+, success leads to sense of closure, don't fear death. Seeing lives as unproductive and being haunted by past mistakes leads to despair.

161

What are the three sites on ribosomes?

P (peptidyl) site, A (amino acyl tRNA site), E (exit)
(also mRNA binding site)

162

What is RT*lnKeq equal to in cal/mol?

-1364*logKeq cal/mol

163

When active, what does MLCP do?

cause relaxation of muscle

164

______, referred to as coenzyme Q or just Q, can accept one or two electrons

ubiquinone

165

What is needed for purine biosynthesis that is not needed for pyrimidine biosynthesis?

THF and Glycine

166

What causes Prader-Willi syndrome?

syndromic obesity, learning difficulties, short stature, compulsive eating (missing dad's copy or there are two maternal copies)

167

GMP and AMP degradation produces _______as a by-product. A build up in this chemical causes ______

uric acid, gout

168

Non-specific NSAIDs block the constitutive pathway of COX1. Normally, COX1 produces _________ that promote the production of mucus lining protecting the inner stomach and _______ which induces platelet aggregation

prostaglandins, thromboxane 2

169

Lesch-Nyhan syndrome, a self-mutilation disease, is caused by a defect in the ________________ step of the salvage pathway

G/HX-PRT

170

In Fragile X syndrome, repeats are located ______ of _____ site, and expansion causes hypermethylation which _____________

upstream, AUG start, inhibition of transcription

171

List the following in order of delta G naught from least negative to most negative:
Anhydrides (ATP)
Guanidium Phosphate (CEP)
Enoyl Phosphate (PED)
Esters (Amides)
Thiolesters (acetyl Coa)

esters (amide), thiol esters (acetyl Coa), anhydrides (ATP), guanidium phosphate (CEP), enoyl phosphate (PED)

172

Class V PDE inhibitors include Levitra, Cialis, Viagra and Sildenafil. How do these increase relaxation of smooth muscle?

PDE breaks down cGMP normally, if inhibited no breakdown of cGMP --> more relaxation
(arteries dilated but veins constricted)

173

Describe the age and conflict of a child in the genital stage

puberty-death, previous struggles may lead to more repression and add'l defenses against conscious sexuality

174

Name 4 common SSRI's

Lexapro, Prozac, Paxil, Zoloft

175

Name four sources of folate

yeast, liver, fruits, green veggies

176

Electron carriers NADH and FADH2 both have oxidation energies equal to delta G naught =

-15 kcal/mol

177

In smooth muscles, when Ca++ increases, ______ is activated which causes phosphorylation of LC50 and increase in contraction

MLCK

178

Describe the trust vs mistrust stage of Erikson

B-18 months, corresponds to oral phase of Freud, if consistent and stable caregiver than child will have hope and self confidence

179

Summarize the differences between purine and pyrimidine synthesis

Purine starts with PRPP then built around it; pyrimidine has PRPP added to NMP (in salvage pathway) or added to orotate (in UMP synthesis)

180

True or false : Highly methylated areas tend to be more transcriptional active

FALSE, less active, DNA methylation patterns are faithfully inherited

181

True or false: A decreased delta G for a reaction lowers Ea barrier

FALSE

182

Glutamine-PRPP amidotransferase is involved in converting glutamine + PRPP to ___________

glutamate

183

Describe the intimacy vs isolation stage of Erikson

18-40 years, love and work compete, avoiding intimacy can lead to isolation, loneliness and depression

184

Describe anticipation

Some dominant disorders manifest at an early age of onset and with increased severity in successive generations. Due to repeat expansion mutation.

185

What enzyme is required to form dNDP from NDP? (deoxy form)

ribonucleotide reductase, disulfide bond has to be reduced after dNDP is synthesized

186

In _______________, rapid loss of central vision due to death of the optic nerve occurs due to 1 of three missense mutations in a mitochondrial protein

Leber's hereditary optic neuropathy (LHON)

187

In the salvage pathway, adenine can be synthesized from bases + PRPP using the enzyme ___________

adenine phospho ribosyl transferase (A-PRT)

188

In the salvage pathway, guanine/hypoxanthine can be synthesized from bases + PRPP using the enzyme ________________

guanine/hypoxanthine phospho ribosyl transferase (G/HX-PRT)

189

______ can act as acceptors or donors in electron transfer. Contains at least 8 iron sulfur proteins.

Iron Sulfur Centers

190

In repeat expansion disorders, what are premutations?

Repeat expansions that are unstable and have dynamic increase in # of repeats in succeeding generations (eventually result in full mutation)

191

___________ inhibits phospholipase A2, which is the __________ in eicosanoid synthesis, an is widely used clinically to treat noninfectious inflammatory diseases

cortisone, first step

192

AMP is synthesized from IMP using _____ wheras GMP synthesized from IMP using ______ (later also produces NADH)

GTP, ATP

193

____________ is essential for proper embryonic development, imprinting, and X inactivation

DNA methyltransferases

194

What are three factors that play a role in targeting mRNA for degradation?

length of poly A tail, binding sites, and types of proteins that bind to it

195

Through ATP synthase, protons are delivered from the ______________ to the ___________ in a process that creates water

intermembrane space, matrix

196

In hydrolytic editing, when an incorrect AA binds to _______ site on tRNA synthetase, the tRNA detects its incorrect and removes it

editing

197

Cytidylate synthetase converts UTP to

CTP

198

Describe what occurs in Complex I of the Electron Transport Chain AKA NADH Dehydrogenase

NADH --> NAD+, 4 H+s are pumped to intermembrane space, FMN serve as electron carriers that transfer e- to Fe-S then Q

199

Describe pernicious anemia

Autoimmune disease that destroys parietal cells

200

What causes Prader-Willi syndrome?

syndromic obesity, learning difficulties, short stature, compulsive eating

201

Describe what occurs in Complex II AKA succinate dehydrogenase

Bound to inner mitochondria membrane, converts succinate to fumarate, produces FADH2, contains binding site for ubiquinone, heme B

202

How is NADH converted to ATP?

oxidative phosphorylation

203

Pyruvate dehydrogenase catalyzes the formation of acetyl CoA from pyruvate and produces NADH. What are the cofactors of this enzyme?

thymine pyrophosphate, lipoic acid, FAD

204

dUMP requires _______ to convert to dTMP and produces DHF as a product. DHF is resynthesized to methylene THF using __________________

methylene THF, dihydrofolate reductase

205

In Fragile X, an unstable trinucleotide repeat ______ will expand only in _______

CGG, mother

206

In the salvage pathway, pyrimidines are synthesized from bases + PRPP using the enzyme _______________

orotic acid transferase

207

Steroid hormones act as ______________ by causing inhibitory proteins on inactive receptors to dissociate thus activating receptors

transcription factors

208

What happens when histones are methylated?

bound very tight, you have silencing or repression

209

What can be used to analyze the severity of disease in repeat expansion disorders (correlates with number of repeats)?

Southern Blot analysis

210

Celebrex is a COX-2 inhibitor used for arthritis pain and inflammation. What is an issue with celebrex?

increase in major vascular events such as nonfatal MI, nonfatal stroke or death from a blood vessel related cause. Upper GI complications such as bleeding, obstructions, perforations

211

True or false: Delta G, Delta H, and/or Delta S give determine reaction rates

FALSE - high activation barrier dictates reaction rates