Biochem Ii

Front 1

Cause of edema, anemia, fatty change in liver, and skin changes

Back 1

Protein malnutrition (Kwashiokur)
(Fatty change in liver due to decreased apolipoproteins)

Front 2

Cause of tissue and muscle wasting

Back 2

energy malnutrition (Marasmus)

Front 3

Cellular site of most fatty acid oxidation (beta oxidation)?

Back 3

mitochondria

Front 4

Cellular site of acetyl-CoA production?

Back 4

mitochondria

Front 5

Cellular site of the citric acid cycle?

Back 5

mitochondria

Front 6

Cellular site of oxidative phosphorylation?

Back 6

mitochondria

Front 7

Cellular site of glycolysis?

Back 7

cytoplasm

Front 8

Cellular site of fatty acid synthesis?

Back 8

cytoplasm

Front 9

Cellular site of HMP shunt?
What types of cells?

Back 9

cytoplasm
lactating mammary glands, liver, adrenal cortex, RBCs

Front 10

Cellular site of protein synthesis?

Back 10

RER, ribosomes (in cytoplasm)

Front 11

Cellular site of steroid synthesis?

Back 11

SER

Front 12

Cellular site of heme synthesis?

Back 12

cytoplasm and mitochondria

Front 13

Cellular site of urea cycle?

Back 13

cytoplasm and mitochondria

Front 14

Cellular site of gluconeogenesis?
What type of cells?

Back 14

cytoplasm and mitochondria
Mostly in the liver (secondarily, kidney and epithelial cells)

Front 15

Cellular site of very long chain and odd-numbered carbon branching fatty acids

Back 15

peroxisomes

Front 16

Uses ATP to add high-energy phosphate group

Back 16

kinases

Front 17

Does not use ATP to add inorganic phosphate

Back 17

phosphorylase

Front 18

Removes phosphate group

Back 18

phosphatase

Front 19

Oxidizes substrate

Back 19

dehydrogenase

Front 20

adds 1 carbon with the help of biotin

Back 20

carboxylase

Front 21

Which glucose kinase is uninduced by insulin?

Back 21

Hexokinase (fasting state --> glycolysis)

Front 22

Which glucose kinase is induced by insulin?

Back 22

glucokinase (fed state --> glycogen synthesis)

Front 23

Ubiquitous enzyme with high affinity, low capacity

Back 23

hexokinase

Front 24

Enzyme found in the liver and beta islet cells of the pancreas, low affinity, high capacity

Back 24

glucokinase

Front 25

Fructose bisphosphatase-2 is active in the __________ state and converts ______________ to ______________

Back 25

Fructose bisphosphatase-2 is active in the fasting state and converts fructose 2,6 bisphosphate to fructose-6-phosphate

Front 26

Phosphofructokinase2 is active in the ________ state and converts ________ to ______________

Back 26

Phosphofructokinase is active in the fed state and converts fructose-6-phosphate to fructose-2,6-bisphosphate

Front 27

The inhibition of what glycolytic cofactor would lead to vomiting, rice water stools, and garlic breath?

Back 27

lipoic acid inhibition from arsenic poisoning

Front 28

What are the 5 cofactors needed in the pyruvate dehydrogenase complex in glycolysis (pyruvate + NAD+ + CoA --> acetyl CoA + CO2 + NADH)?

Back 28

1. thiamine pyrophosphate (TPP)
2. riboflavin (B2) for FAD
3. niacin (B3) for NAD
4. pantothenate (B5) for CoA
5. lipoic acid

Front 29

What is the treatment for pyruvate dehydrogenase deficiency?

Back 29

Food high in ketogenic amino acids (high fat or high lysine and leucine)

Front 30

What does the Cori cycle do?
Where is it?
How much ATP is produced or used?

Back 30

Lactate ---> 2 pyruvate ---> glucose

In the liver

+2 ATP (glycolysis) + 6 ATP - 12 ATP = 4 NET ATP LOST

Front 31

How many of each of the following are produced for each acetyl CoA that enters the TCA?
NADH?
FADH2?
CO2?
GTP?

Back 31

3 NADH
2 CO2
1 FADH2
1 GTP

Front 32

How many ATP are produced via the malate-aspartate shuttle (heart and liver)?
In the glycerol-3-phosphate shuttle (muscle)?

Back 32

malate-aspartate (heart and liver): 32
glycerol-3-phosphate (muscle): 30

Front 33

Name the intermediates of the TCA in order.

Back 33

Cirtrate
Isocitrate
alpha-Ketoglutarate
Succinyl CoA
Succinate
Fumarate
Malate
Oxaloacetate

Front 34

How many ATP are generated via oxidative phosphorylation for each NADH?
For each FADH2?

Back 34

1 NADH --> 3 ATP (starts at complex I)
2 FADH2 --> 2 ATP (starts at complex II)

Front 35

What poisons inhibit electron transport?

Back 35

Rotenone, CN-, antimycin A, CO

Front 36

What poisons inhibit ATPase?

Back 36

Oligomycin

Front 37

What poisons cause increased mitochondrial membrane permeability (uncoupling, generate heat)?

Back 37

2,4-DNP, aspirin, thermogenin in brown fat

Front 38

Irreversible enzyme found in the mitochondria that converts pyruvate to oxaloacetate for gluconeogenesis

Back 38

pyruvate carboxylase

Front 39

What is required for function of pyruvate carboxylase?
What activates it?

Back 39

biotin, ATP

activated by acetyl CoA

Front 40

Irreversible enzyme found in the cytosol that converts fructose 1,6-bisphosphate to fructose-6-phosphate for gluconeogenesis

Back 40

fructose-1,6-phosphatase

Front 41

Irreversible enzyme found in the ER that converts glucose-6-phosphate to glucose for gluconeogenesis

Back 41

glucose-6-phosphatase

Front 42

Irreversible enzyme found in the cytosol that converts oxaloacetate to phosphoenolpyruvate for gluconeogenesis

Back 42

PEP carboxykinase (requires GTP)

Front 43

What type of fatty acids can enter gluconeogenesis? How?

Back 43

only odd-chain fatty acids; enter TCA as succinyl CoA

(even-chain make acetyl CoA equivalents)

Front 44

A black patient's blood smear shows Heinz bodies (Hb precipitate) and bite cells. What foods/drugs should HE avoid?

Back 44

G6PD DEFICIENCY (X-linked recessive --> inability to regenerate NADPH to keep glutathione reduced --> RBCs subject to oxidizing agents)

fava beans
primaquine
sulfonamides
anti-TB drugs

Front 45

A pt has hypoglycemia, jaundice, cirrhosis, vomiting.
What is the enzyme deficiency?
What is the inheritance pattern?
What is the treatment?

Back 45

FRUCTOSE INTOLERANCE

- Lack of aldolase B --> buildup of fructose-1-phosphate, uses up phosphate --> hypoglycemia
- autosomal recessive
- reduce consumption of fructose and sucrose

Front 46

A pt is asymptomatic except their blood and urine have fructose in them.
What is the enzyme deficiency?
What is the inheritance pattern?

Back 46

ESSENTIAL FRUCTOSURIA
- lack of fructokinase
- autosomal recessive

Front 47

An infant has failure to thrive, hepatomegaly, infantile cataracts, mental retardation
What is the enzyme deficiency?
What is the inheritance pattern?
What is the treatment?

Back 47

CLASSIC GALACTOSEMIA
- galactose-1-P-uridyltransferase deficiency
- AR
- exclude galactose and lactose

Front 48

An infant presents with infantile cataracts, galactose in blood and urine, failure to track objects, no social smile.
What is the enzyme deficiency?
What is the inheritance pattern?
What is the treatment?

Back 48

GALACTOKINASE DEFICIENCY
- galactokinase deficiency
- AR
- exclude galactose and lactose

Front 49

What causes infantile cataracts in essential galactosemia and galactokinase deficiency?

Back 49

Buildup of galactitol in the lens of the eye

Front 50

Why are the Schwann cells, lens, retina, and kidneys of diabetic patients particularly vulnerable to damage?

Back 50

Those tissues have aldose reductase but not sorbitol dehydrogenase --> buildup of osmotically active sorbitol

Front 51

Which essential amino acids are only glucogenic?

Back 51

Met, Val, Arg, His

Front 52

Which essential amino acids are both glucogenic and ketogenic?

Back 52

Ile, Phe, Thr, Trp

Front 53

Which amino acids are only ketogenic?

Back 53

Leucine, Lysine (give in pyruvate dehydrogenase deficiency)

Front 54

Which amino acids are most necessary during periods of growth?

Back 54

arginine and histine

Front 55

Which amino acids are highest in content in histones?

Back 55

Arginine and lysine (negative)

Front 56

Urea is composed of nitrogen and carbon from what original sources?

Back 56

NH4+ (N), CO2 (C=O), and aspartate (N)

Front 57

A pt presents with tremor, slurring of speech, somnolence, vomiting, cerebral edema, and blurring of vision
- Cause in an adult?
- Cause in a small child?
- Treatment?

Back 57

Ammonia toxicity

- liver disease (hepatic encephalopathy)
- urea cycle disorder (e.g. ornithine decarbamoylase deficiency)
- reduce protein in diet, give benzoate or phenylbutyrate to bind amino acid

Front 58

Pt presents with orotic acid in blood and urine, decreased BUN, symptoms of hyperammonemia
- What is the enzyme defect?

Back 58

ornithine trasnscarbamoylase deficiency

(ddx from orotic aciduria, which has no associated hyperammonemia)

Front 59

What breakdown products would be seen in the urine from the actions of MAO and COMT on the following neurotransmitters:
- dopamine
- norepinephrine
- epinephrine

Back 59

- dopamine --> homovanillic acid
- norepi --> VMA
- epinephrine --> metanephrine

Front 60

A young child has mental retardation, growth retardation, seizures, fair skin, eczema, musty body odor. What enzyme(s) could he be lacking?

Back 60

PKU!

phenyalanine hydroxylase or its tetrahydrobiopterin cofactor

Front 61

An infant's urine shows elevated phenylacetate, phenyllactate, and phenylpyruvate. What is her treatment?

Back 61

PKU (elevated phenylketones)

No Phe in diet, supplement with Tyr

Front 62

A pt has dark connective tissue, pigmented sclera, and her urine turns black on standing. She complains of debilitating joint pain. What enzyme is she missing?

Back 62

ALKAPTONURIA

homogentisic acid oxidase (breaks down Tyr)

Front 63

A pt has a lack of tyrosinase. What cancer is she at risk for?

Back 63

ALBINO (Tyr --> melanin)

squamous cell carcinoma

Front 64

A pt has mental retardation, osteoporosis, tall stature, kyphosis, lens subluxation, and atherosclerosis.
What dietary modifications should be met?

Back 64

- decreased Met, increased Cys, increased B12 and folate (cystathionine synthase deficiency)
- big increased B6 (decreased affinity for pyridoxal phosphate cofactor)

Front 65

Treatment for cystine kidney stones?
Defect?

Back 65

Acetazolamine to alkalinize urine
Renal amino acid transporter in PCT

Front 66

A pt with severe CNS defects, retardation, and sweet-smelling urine would likely exhibit excesses of which amino acids in the blood?

Back 66

Ile, Leu, Val (branched aa's)

MSUD - decreased alpha-ketoacid dehydrogenase

Front 67

A pt with diarrhea, dementia, and dermatitis has a defective transporter where?

Back 67

on renal and intestinal epithelial cells --> excretion of tryptophan (neutral aa) --> inability to make niacin

Front 68

A pt presents with severe fasting hypoglycemia, very high liver glycogen, high blood lactate, hepatomegaly. Enzyme deficiency?

Back 68

Glucose-6-phosphatase

VON GIERKE'S DISEASE
(Type I glycogen storage disorder)

Front 69

A pt presents with cardiomegaly and systemic findings, increased glycogen in liver and muscle. Enzyme deficiency?

Back 69

lysosomal 1,4-glucosidase

POMPE'S DISEASE
(Type II glycogen storage disorder)

Front 70

A pt presents with fasting hypoglycemia, high liver glycogen, normal blood lactate, mild hepatomegaly. Enzyme deficiency?

Back 70

debranching enzyme

CORI'S DISEASE
(Type III glycogen storage disorder; milder than type I because gluconeogenesis is intact)

Front 71

A pt presents with painful muscle cramps and myoglobinuria (dark urine) with strenuous exercise. Enzyme deficiency?

Back 71

Skeletal muscle glycogen phosphorylase

MCARDLE'S DISEASE
(Type V glycogen storage disorder)