Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

STEP 1 > High Yield Topics-Biochemistry > Flashcards

High Yield Topics-Biochemistry Flashcards

1
Q

On NBME, do you ever refer or send patient to ethics committee?

A

NO! NEVER!

Use patient-centered questions, respect patient autonomy, never lie

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Inheritance pattern of mostly enzyme deficiencies; usually seen in only 1 generation

A

AR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Inheritance pattern of mostly structural protein gene defect; usually seen in many generations with variable expressivity

A

AD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How to distinguish x-linked dominant vs. recessive

A

x-linked dominant: females are more affected

x-linked recessive: males are more affected

  • no male to male transition in both types!
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

One gene contributes to multiple phenotypic effects; example is PKU ( light skin, intellectual disability, and musty body odor)

A

Pleiotropy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Presence of both normal and mutated mtDNA, resulting in variable expression in mitochondrially inherited disease

  • mtDNA passed from mother to all children.
A

Heteroplasmy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

inheritance that occurs when one characteristic is controlled by two or more genes

A

Polygenic inheritance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

When gene is “silenced”

A

imprinting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

A disorder caused by paternal uniparental disomy with paternal imprinting and maternal deletion; Inappropriate laughter, seizures, ataxia, severe intellectual disability

A

Angelman syndrome

  • STUDY AID: angelMEN syndrome is paternal uniparental disomy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

A disorder caused by maternal uniparental disomy with maternal imprinting and paternal deletion; Hyperphagia and obesity, intellectual disability, hypogonadism, hypotonia

A

Prader-Willi syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

immotile cilia (cilliary dyskinesia) due to a dynein arm defect; decreased male and female fertility due to immotile sperm and dysfunctional fallopian tube cilia; cause bronchiectasis, recurrent sinusitis, chronic ear infections, conductive hearing loss, and situs inversus (dextrocardia on xray)

A

Kartagener syndrome

  • Kartagener’s restaurant: take-out only –> there’s no dynein “dine-in”
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Inheritance pattern of Kartagener syndrome

A

AR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Normal function of CFTR gene

A

CFTR gene encodes ATP-gated Cl- channels –> secrete Cl- in lungs & GI tract and reabsorb Cl- in sweat glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Inheritance pattern of CF

A

AR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe pathophysiology of CF

A
  1. Phe508 deletion in CFTR gene on chromosome 7
  2. Misfolded protein –> protein reatined in RER and cannot be transported to cell membrane
  3. Cl- cannot be secreted –> Increased intracellular Cl-
  4. Compensatory Na+ reabsorption via ENaC channel (and H2O follows)
  5. Abnormal thick mucus secreted in lungs and GI tract
  6. Na+ and Cl- cannot be reabsorbed in sweat glands –> excessive NaCl salt (and water) losses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How is CF diagnosed?

A

Adults: Increased Cl− concentration in pilocarpine-induced sweat test

Newborn Screening: increased immunoreactive trypsinogen

  • pilocarpine is cholinergic agonist (increase sweating)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What electrolyte abnormality can be present in CF patients due to renal K+/H+ wasting in order to compensate ECF Na+/H2O losses (through sweating)?

HINT: effects are similar to taking a loop diuretic

A

contraction (metabolic) alkalosis & hypokalemia

  • K+/H+ ATPase moves K+ and H+ in opposite directions –> H+ moves into the cell & K+ moves out of the cell –> Hypokalemia & metabolic alkalosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Pulmonary complications associated with CF

A

Recurrent pulmonary infections, chronic bronchitis, and bronchiectasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

GI-related complications associated with CF

A

Pancreatic insufficiency, malabsorption with steatorrhea, fat-soluble vitamin deficiencies, and meconium ileus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

a bowel obstruction that occurs in CF babies when the meconium in your child’s intestine is even thicker and stickier than normal meconium

A

meconium ileus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What other clinical signs/symptoms are associated with CF

A

infertility in men (subfertility in women), clubbing of nails, and nasal polyps

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Tx for pancreatic insufficiency due to CF

A

Pancreatic enzyme replacement therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Tx for phe508 deletion in CF (2 types)

A
  1. lumacaftor (corrects misfolded proteins and improves their transport to cell surface)
  2. ivacaftor (increase opening of Cl– channels → improved chloride transport)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Both b-oxidation (FA oxidation) and ketogenesis occur in what organelle?

A

mitochondria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Glycolysis occurs in what part of the cell?

A

cytoplasm/cytosol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Heme synthesis, urea cycle, and gluconeogenesis occur in what organelle?

A

both cytoplasm and mitochondria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Enzyme that muscle lacks and therefore cannot participate in gluconeogenesis

A

glucose-6-phosphatase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Even/Odd chain FA can undergo gluconeogenesis (enter the TCA cycle as 1 propionyl-CoA) and serve as a glucose source

A

Odd chain FA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

glucose-6-phosphatase resides in what organelle to convert Glucose-6-phosphate to glucose?

A

ER

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Pentose phosphate pathway is aka

A

HMP shunt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

HMP shunt provides what two important products from glucose-6-phosphate

A
  1. NADPH (required for many reductive rxns)

2. ribose-5-phosphate (nucleotide synthesis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What enzyme converts glucose-6P to 6-phosphogluconate (and reduces NADP+ to NADPH)?

A

Glucose-6-phosphate dehydrogenase (G6PD)

  • G6PD deficiency leads to anemia (heinz bodies & bite cells)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Tyrosine, DOPA, dopamine, NE, and epinephrine are what amino acid derivates?

A

Phenylalanine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Niacin (B3) and serotonin are what amino acid derivates?

A

Tryptophan

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Histamine is what amino acid derivates?

A

Histidine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Porphyrin and heme are what amino acid derivates?

A

Glycine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

GABA and glutathione are what amino acid derivates?

A

Glutamate

glutamate is not same as glutamine; two different AAs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

creatinine, urea, and nitric oxide are what amino acid derivates?

A

Arginine

  • STUDY AID: creatinine sounds like creatine
  • You need “creatinine” to build muscle (arghhh)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Nonpolar or hydrophobic amino acids

A

GLAM VIP PT

Glycine
Leucine
Alanine
Methionine

Valine
Isoleucine
Phenylalanine

Proline
Tryptophan

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What are the steps, enzymes, and cofactors in catecholamine synthesis?

A
  1. phenylalanine to tyrosine
    - by phenylalanine hydroxylase
    - BH4
  2. tyrosine to DOPA
    - by tyrosine hydroxylase
    - BH4
  3. DOPA to dopamine
    - by DOPA decarboxylase
    - B6
  4. dopamine to NE
    - by dopamine B-hydroxylase
    - Vitamin C
  5. NE to Epinepherine
    - by PMNT
    - S-Adenosyl methionine (SAM)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What enzyme converts tyrosine to melanin?

A

Tyrosinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Enzyme affected in PKU

A

phenylalanine hydroxylase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Enzyme affected in albinism

A

Tyrosinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Congenital deficiency of homogentisate oxidase in the degradative pathway of tyrosine to fumarate; causes pigment-forming homogentisic acid builds up in tissue; presents with dark urine (when exposed to air), ochronosis (bluish-black connective tissue like in ear cartilage and sclerae), and arthralgias (homogentisic acid builds up in joints)

A

alkaptonuria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

A disorder due to decreased phenylalanine hydroxylase or decreased tetrahydrobiopterin (BH4) cofactor; presents with intellectual disability, growth retardation, seizures, fair complexion, eczema, musty body odor

A

Phenylketonuria (PKU)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

A disorder affecting infants due to lack of proper dietary therapy during pregnancy; presents with microcephaly, intellectual disability, growth retardation, congenital heart defects

A

Maternal PKU

*Mother has PKU which affects infant growth during pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

PKU patients must avoid what artificial sweetener since it contains phenylalanine

A

aspartame

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Enzyme affected in alkaptonuria

A

homogentisate oxidase

  • converts Homogentisic Acid to Maleylacetoacetic Acid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Enzyme that destroys damaged or ubiquitin-tagged proteins; defective in “Parkinson disease”

A

Proteasome

*Defects in the ubiquitin-proteasome system have been implicated in some cases of Parkinson disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

An organelle that plays a key role in apoptosis; Cytochrome C leaks into the cell from this organelle and activates caspases, which break down cellular proteins

A

Mitochondria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Stabilize the inter mitochondria membrane, which prevents leakage of Cytochrome C into the cell

A

Bcl-2 and Bcl-xL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What cells lack Mitochondria?

A

RBCs (it needs to carry O2 and not used by mitochondria)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What autoimmune disorder is associated with anti-mitochondrial antibodies?

A

Primary Biliary Cholangitis (bile ducts in liver)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Most common type of collagen; makes bone, skin, tendon, cornea, LATE wound repair

A

Type I: bONE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Type of collagen that makes cartilage, hyaline, vitreous humor, and nucleus pulposus

A

Type II: carTWOlage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Type of collagen that makes blood vessels, uterus, early wound repair, and “reticulin” in connective tissue

A

Type III

  • STUDY AID: parallel lines look like blood vessels
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Collagen type deficient in Ehlers-Danlos syndrome

A

Type III or V

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Type of collagen that makes lens and basement membrane (lamina)

A

Type IV: four for floor (BM)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Collagen type deficient in Alport syndrome

A

Type IV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Collagen type targeted by antibodies in Goodpasture syndrome

A

Type IV

  • STUDY AID: “Good Pastor is ANTI-satan”
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Collagen is synthesized by

A

fibroblasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Describe steps of collagen synthesis

A
  1. Preprocollagen Synthesis:
    - collagen a-chains (Glycine-Proline-Lysine) are translated in RER
  2. Hydroxylation:
    - Proline and lysine are hydroxylated
    - Vitamin C is required!
  3. Glycosylation:
    - Hydroxylysine residues are glycosylated
    - Three glycosylated collagen a-chains are bonded via hydrogen and disulfide bonds
    - Procollagen forms (triple helix of 3 a-chains)
  4. Exocytosis:
    - procollagen is exocytosed into extracellular space (outside of cell)
  5. Proteolytic Processing:
    - C and N terminals of procollagen are cleaved
    - Tropocollagen forms
  6. Cross-linking:
    - lysyl oxidase covalently link many tropocollagens via lysine-hydroxylysine bonds
    - Copper is required!
    - Collagen fibers form
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Vitamin C deficiency can impair what collagen synthesis step and cause what disease?

A

hydroxylation of proline and lysine; Scurvy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Problems forming triple helix can cause what disease?

A

Osteogenesis imperfecta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Problems with cross-linking is caused by what disease?

A

Menkes disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

↓ production of otherwise normal type 1 collagen due to problems forming triple helix; presents with multiple fractures after minimal trauma, blue sclerae, tooth abnormality, and hearing loss

A

Osteogenesis imperfecta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

Inheritance pattern of Osteogenesis imperfecta

A

AD

  • structural protein defect
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Tx for Osteogenesis imperfecta

A

bisphosphonates to ↓ fracture risk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Gene defects of Osteogenesis imperfecta

A

COL1A1 and COL1A2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Connective tissue disease caused by impaired copper absorption and transport due to defective Menkes protein; presents with brittle, “kinky” hair, growth retardation, hypotonia, and ↑ risk of cerebral aneurysms

A

Menkes disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

What enzyme activity is low due to impaired copper absorption in Menkes disease?

A

lysyl oxidase

*copper is a necessary cofactor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

Gene defects of Menkes disease

A

ATP7A

  • ATP7B in Wilson disease (causes high level of copper instead of low as in Menkes disease)
  • STUDY AID: a (means to lack)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

Inheritance pattern of Menkes disease

A

X-Linked recessive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Faulty collagen synthesis causing hyperextensible skin, hypermobile joints, and tendency to bleed (easy bruising); AD inheritance

A

Ehlers-Danlos syndrome

  • collagen type III or V mutation
75
Q

Collagen type that causes hyperextensible skin and hypermobile joints in Ehlers-Danlos syndrome

76
Q

Collagen type that causes Vascular defects (bleeding, berry/aortic aneurysm, and uterus that are prone to rupture)

77
Q

Protein that is NOT hydroxylated and can stretch

78
Q

Amino acids that form elastin

A

Nonhydroxylated proline, glycine, and lysine residues

79
Q

A glycoprotein that forms a sheath around elastin; acts as a scaffold

80
Q

Cross-linking of many tropoelastins occur in

A

extracellular space

*same as collagen cross-linking

81
Q

Enzyme that breaks down elastin

82
Q

Elastase is normally inhibited by

A

a1-antitrypsin

83
Q

a1-antitrypsin deficiency results in unopposed elastase activity and can cause what disease?

A

Emphysema (COPD)

84
Q

Although dermal collagen and elastin synthesis decreases with age, what remains normal?

A

cross-linking

85
Q

Defective fibrillin causes what disorder that presents with tall stature, long extremities and fingers/toes, pectus excavatum (sunken chest), hypermobile joints, aortic root dilation/aneurysm, and mitral valve prolapse?

A

Marfan syndrome

86
Q

Gene mutation of Marfan syndrome

A

FBN1 gene –> defective fibrillin

*STUDY AID: “MARk zukerberg is the #1 CEO of FB” (FBn1)

87
Q

How do you distinguish Marfan syndrome vs. Homocystinuria?

A

Marfan syndrome:

  • upward displacement of lens
  • aortic root dilation/aneurysm
  • normal intellectual ability

Homocystinuria:

  • downward displacement of lens
  • No aortic involvement
  • Intellectual disability
88
Q

Describe insulin synthesis

*HINT: similar to collagen synthesis!

A
  1. Preproinsulin is synthesized in RER of pancreatic B-cells
  2. Presignal is cleaved to form proinsulin
  3. Proinsulin is cleaved again and exocytosed with c-peptide in secretory granules
89
Q

What level is elevated with insulin in insulinoma and sulfonylurea use?

A

C-peptide

*it means endogenous insulin production

90
Q

What is missing if insulin is from exogenous source?

91
Q

Niacin is aka

92
Q

Niacin is derived from what amino acid?

A

tryptophan

93
Q

Constituent of NAD+ and NADP+ (used in redox reactions); lowers levels of VLDL and raises levels of HDL (used to treat dyslipidemia)

94
Q

Deficiency leads to glossitis (swollen, inflamed tongue), facial flushing, and pellagra (diarrhea, dementia, dermatitis, and death)

95
Q

“broad collar” rash (Casal necklace) and hyperpigmentation of sun exposed are skin findings of

A

dermatitis of niacin deficiency

96
Q

Deficiency of neutral amino acid (tryptophan) transporters in proximal renal tubular cells and on enterocytes —–> neutral aminoaciduria and decreased absorption from the gut —–> decreased tryptophan for conversion to niacin leading to pellagra

A

Hartnup Disease

97
Q

Niacin is found in what type of food

A

meat/protein

98
Q

Vitamin B12 is aka

99
Q

Cofactor for DNA synthesis, myeline synthesis, and methionine synthase (converts homocysteine to methionine)

A

Vitamin B12

100
Q

Deficiency leads to macrocytic, megaloblastic anemia, hypersegmented PMNs, and nerve damage (myelin degeneration)

A

Vitamin B12

101
Q

Lab findings for macrocytic, megaloblastic anemia caused by vitamin B12 deficiency

A

Increased MMA

Increased homocysteine

102
Q

Macrocytic, megaloblastic anemia caused by folic acid does not have elevated

103
Q

Vitamin B12 is found only in what type of food?

A

Animal products

104
Q

An autoimmune gastritis that destroys Parietal Cells and leads to HCl acid and Intrinsic Factor deficiency –> B12 deficiency

A

Pernicious anemia

105
Q

B12 deficiency can also be caused by what surgery?

A

gastric bypass surgery; Crohn disease surgery (surgical resection of ileum)

106
Q

What unique symptom in B12 deficiency can help distinguish from folate deficiency?

A

neurologic symptom

*not present in folate deficiency

107
Q

A long-term veganism can lead to what type of anemia?

A

macrocytic, megaloblastic anemia (B12 deficiency)

  • takes a very long time though!
108
Q

Deficiency presents as hemolytic anemia, acantholysis (loss of cohesion between keratinocytes), and demyelinations of the dorsal columns and spinocerebellar tract

109
Q

Vitamin E is aka

A

tocopherol

110
Q

Excess can increase risk of enterocolitis in infant. May also decrease metabolism of vitamin K, thereby enhancing warfarin effects

111
Q

ALT vs. AST in liver disease

112
Q

ALT vs. AST in alcoholic liver disease

A

AST > ALT

  • AST will not exceed 500 U/L in alcoholic hepatitis
  • AST/ALT > 2
113
Q

AST > ALT in nonalcoholic liver disease suggests

A

cirrhosis (a late stage of scarring (fibrosis) of the liver)

114
Q

AST, ALT > 1000 U/L suggests

A
  1. drug-induced liver injury (acetaminophen toxicity)
  2. ischemic hepatitis
  3. acute viral hepatitis
  4. autoimmune hepatitis
115
Q

Antibodies associated with pernicious anemia

A
  1. anti-parietal cells

2. anti-IF

116
Q

What trisomy causes rocker-bottom feet, cleft liP/Palate, Polydactyly, cutis aplasia (absence of skin on scalp), Polycystic kidney disease, and omphalocele (covered)?

A

Patau syndrome

  • trisomy 13 = “P”uberty age
  • Caused by oligohydramnios
117
Q

What trisomy is due to defect in fusion of prechordal mesoderm → midline defects

A

Patau syndrome

118
Q

What trisomy causes clenched fists with overlapping fingers, rocker-bottom feet, prominent occiput, low-set ears, and micrognathia (small jaw)?

A

Edwards syndrome

  • trisomy 18 = “E”lection age
119
Q

What trisomy causes flat facies, single palmar crease, duodenal atresia, ASD, and Brushfield spots (speckled iris)?

A

Down

*trisomy 21 = “D”rinking age

120
Q

Patients with down syndrome are at an increased risk of developing

A
  1. Alzheimer disease
    (chromosome 21 codes for amyloid precursor protein)
  2. AML/ALL
121
Q

Two types of genetic mutation causing down syndrome

A
  1. 95% of cases due to “meiotic nondisjunction”

2. 4% of cases due to “unbalanced Robertsonian translocation” (b/w chromosomes 14 and 21)

122
Q

Risk of meiotic nondisjunction mutation that cause down syndrome increases with

A

advanced maternal age

123
Q

Markers for down syndrome during pregnancy

A

Decreased AFP
Increased hCG
Increased inhibin

    • nuchal translucency
124
Q

Mnemonic for Fabry Dx

A

My fabryite activity is making ceramic galaxy. Sorry for keep HARPing on it.

125
Q

Describe Fabry Dx

A
  • Ceramide accumulation
  • Galactosidase deficiency
  • H: Hypohidrosis
  • A: Angiokeratomas
  • R: Renal failure
  • P: Peripheral neuropathy
126
Q

Mnemonic for Gaucher Dx

A

(crying voice) OMGauch! He’s such a bro.

127
Q

Describe Gaucher Dx

A
  • Glucocerebroside accumulation
  • Glucocerebrosidase deficiency
  • O: Osteoporosis
  • M: Most common LSD
  • G: Gross femoral avascular necrosis
  • Lipid-laden tissue paper cytoplasm
128
Q

Mnemonic for Tay-Sachs Dx

A

A gang of six small Jews

129
Q

Describe Tay-Sachs Dx

A
  • Ganglioside accumulation
  • Hexoaminidase A deficiency
  • No hepatosplenomegaly
  • Cherry-red spots on macula
130
Q

Mnemonic for Niemann-Pick Dx

A

Pick your nose with a big, foamy sphinger

131
Q

Describe Niemann-Pick Dx

A
  • Sphingomyelin accumulation
  • Sphingomyelinase deficiency
  • Yes hepatosplenomegaly
  • Cherry-red spots on macula
  • Foam cells (lipid-laden macrophages)
132
Q

Mnemonic for Krabbe Dx

A

A glob of GOOey krabbe meat is out of this world

133
Q

Describe Krabbe Dx

A
  • Galactocerebroside accumulation
  • Galactocerebrosidase deficiency
  • G: Globoid cells
  • O: Oligodendrocyte destruction
  • O: Optic atrophy
134
Q

Mnemonic for Metachromatic Leukodystropy

A

Metapod is an aryl broken pokemon

135
Q

Describe Metachromatic Leukodystropy

A
  • Cerebroside sulfate accumulation
  • Arylsulfatase deficiency
  • Dementia
  • Ataxia
  • Central/peripheral demyelination
136
Q

Mnemonic for Hunter syndrome

A

Hunters have clear I’s 2 see

137
Q

Describe Hunter syndrome

A
  • Dermatan/heparan sulfate accumulation
  • Iduronate-2-sulfatase deficiency
  • Gargoylism (coarse facial features)
  • No corneal clouding
  • Behavioral aggression
138
Q

Describe Hurler syndrome

A
  • Dermatan/heparan sulfate accumulation
  • Alpha-2-iduronitase deficiency
  • Gargoylism (coarse facial features)
  • Corneal clouding
139
Q

What lysosomal storage diseases are x-linked recessive

A

Hunter
Fabry

“Hunt FoX”

140
Q

What lysosomal storage diseases are autosomal recessive

A

Everything else besides Hunter & Fabry

141
Q

Enzymes of Glycolysis

  1. Insulin activates _____
  2. Glucagon activates _____
A
  1. Phosphofructokinase-2

2. Fructose-2,6-bisphosphatase

142
Q

Rate-limiting enzyme in glycogen synthesis

A

glycogen synthase

143
Q

Rate-limiting enzyme in glycogenolysis

A

Glycogen phosphorylase

144
Q

Mnemonic for Von Gierke Disease

A

Von “Geek” Disease

  • Fat, fatty liver, and no muscle
145
Q

Describe Von Gierke Disease

A
  • Lack of G-6-phosphatase
  • Hepatomegaly
  • Hypoglycemia (no gluconeogenesis)
  • Hyperlipidemia (increased fat breakdown)
  • Hyperuricemia (increased protein breakdown)
  • Since glucose cannot be made, fat & protein catabolism increases
146
Q

Mnemonic for Cori Disease

A

“Coral” disease

  • Think of coral reef
147
Q

Describe Cori Disease

A
  • Lack of debranching enzyme (alpha-1,6-glucosidase)
  • Abnormal glycogen structure (like branched coral reef)
  • Same symptoms as Von Gierke Disease
148
Q

Mnemonic for McArdle’s Disease

A

McArdle’s-“Muscle”

149
Q

Describe McArdle’s Disease

A
  • Lack of glycogen phosphorylase in “muscle”
  • Muscle cramps on exertion
  • Hypoglycemia on exertion
  • Myoglobinuria (glycogen deposit damages and increases muscle breakdown)
  • glycogen phosphorylase cleaves 1,4-a-glycosidic bonds
150
Q

Mnemonic for Her’s Disease

A

Her’s-“Hepatic”

151
Q

Describe Her’s Disease

A
  • Lack of glycogen phosphorylase in “hepatocytes”
  • Hepatomegaly
  • Fasting blood hypoglycemia
152
Q

Mnemonic for Anderson Disease

A

“Anderson Cooper gets straight to the point”

153
Q

Describe Anderson Disease

A
  • Lack of branching enzyme

- Cirrhosis (long glycogen constantly inflamed the liver –> scarring)

154
Q

Mnemonic for Pompe Disease

A

“Pompe affects the pumping organ (heart)”

155
Q

Describe Pompe Disease

A
  • Lack of debranching enzymes specifically in “lysosomes”

- Cardiomegaly (heart has lots of lysosomes)

156
Q

Periodic acid-Schiff stain identifies what molecule and is useful identifying diseases related to this molecule?

157
Q

Symptoms/signs that develop with tyrosine hydroxylase deficiency

A

Decreased dopamine –> progressive “dystonia”

Decreased dopamine –> decreased “Homovanillic Acid” (dopamine degradation products)

158
Q

Cotransporter that absorbs galactose and glucose through the intestinal enterocytes.

A

sodium-glucose cotransporter-1 (SGLT-1)

  • SGLT2 is responsible for Na+ and glucose reuptake in the KIDNEY (PCT)
159
Q

Rising from supine to standing results in what changes (dec. or inc.) in venous return, carotid sinus baroreceptor activity, and cerebral blood flow?

A
  • decreased venous return
  • decreased carotid sinus baroreceptor activity (due to decreased atrial stretching)
  • decreased cerebral blood flow
160
Q

a genetic phenomenon in which disease traits are more severe and/or appear at earlier ages in later generations

A

Anticipation

161
Q

Anticipation is commonly seen in what type of genetic phenomena?

A

trinucleotide repeat expansions

162
Q

Trinucleotide repeat expansions is a genetic mutation caused by a defect in

A

DNA mismatch repair

163
Q

Progressive skeletal muscle wasting, weakness (impaired ability to relax), and cardiomyopathy with dysrhythmia (arrhythmia)

A

Myotonic dystrophy

164
Q

What trinucleotide repeat expansion of ____ gene causes myotonic dystrophy

A

CTG; DMPK (dystrophia myotonica protein kinase)

165
Q

What lysosomal storage diseases show increased urinary levels of dermatan and heparan sulfates (mucopolysaccharides)?

A

Hunter & Hurler Syndromes

166
Q

Mucopolysaccharides are currently known as

A

glycosaminoglycans (GAGs)

167
Q

An autosomal recessive disease similarly presents as Hurler syndrome (coarse facial feature, corneal clouding) that is caused by defective N-acetylglucosaminyl-1-phosphotransferase

A

I-cell disease

168
Q

Defective N-acetylglucosaminyl-1-phosphotransferase in I-cell disease causes impaired addition of _____ to lysosomal enzymes

A

mannose phosphate

169
Q

The same phenotype can be produced by numerous different gene mutations

ex. Albinism

A

Genetic heterogeneity

  • two affected individuals can exhibit the same symptoms of albinism but have entirely disparate genetic mutations.
170
Q

Changes in the following enzyme activity or molecule concentrations during fasting (dec or inc)

  1. fructose 2,6-bisphosphate
  2. glucose 6-phosphatase
  3. phosphoenolpyruvate carboxykinase
  4. pyruvate kinase
A
  1. dec
  2. inc
  3. inc
  4. dec
171
Q

Describe adenylate cyclase signaling pathway

A
  1. Ligand binds to GPCR
  2. GPCR goes through conformational change and activates alpha subunit
  3. Alpha subunit releases GDP and binds to GTP
  4. GTP bound alpha subunit activates adenylate cyclase
  5. adenylate cyclase converts ATP into cAMP
  6. cAMP binds to inhibitory protein on Protein Kinase “A”
  7. Activated PKA activates protein kinase
  8. Activated protein kinase activates other enzymes (ex. glycogen phosphorylase)
172
Q

Type of G protein that involves adenylate cyclase

A 
G stimulatory (Gs)
G inhibitory (Gi)
173
Q

Describe phospholipase C signaling pathway

A
  1. Ligand binds to GPCR
  2. GPCR goes through conformational change and activates alpha subunit
  3. Alpha subunit releases GDP and binds to GTP
  4. GTP bound alpha subunit activates phospholipase C
  5. phospholipase C cleaves PIP2 molecule –> IP3 & DAG
  6. IP3 binds to IP3/Ca+2 channel on ER
  7. Ca+2 gets released into cytosol
  8. Cytosolic Ca+2 and DAG together activates protein kinase “C”
  9. Activated PKC phosphorylates target protein
174
Q

Type of GCPR that involves phospholipase C

175
Q

Pyruvate –> acetyl coa is mediated by what enzyme?

A

Pyruvate dehydrogenase (complex)

176
Q

What serum level increases in pyruvate dehydrogenase deficiency?

A

Lactic acid (b/c pyruvate can only be converted to lactate by LDH)

177
Q

What type of amino acids can provide energy in the form of acetyl-CoA without increasing lactate production?

A

Ketogenic amino acids

  • Lysine
  • Leucine
178
Q

What type of amino acids can produce pyruvate or TCA cycle intermediates, which can be converted to glucose via gluconeogenesis?

A

Glucogenic amino acids

- all AAs except Lysine and Leucine!

179
Q

In response to increased exercise, what locally produced metabolites (5) from skeletal muscles are produced? What’s their function?

A
  • Lactate, H+, K+, CO2, and Adenosine

- Vasodilation

180
Q

Accumulation of NADH is observed in the setting of tissue

A

Hypoxia

  • Without oxidative phosphorylation, the body increases glycolysis to generate ATP ANaerobically, which produces excess NADH and lactic acid
181
Q

C-ANCA is antibody against

A

cytoplasmic components of “neutrophils”

182
Q

P-ANCA is antibody against

A

Peri-nuclear components of “neutrophils”

183
Q

C-ANCA is aka.

A

Proteinase 3 (PR3) antibody

184
Q

P-ANCA is aka.

A

Myeloperoxidase (MPO) antibody

STEP 1 (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions