Brainscape's Knowledge GenomeTM

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


See full index

STEP > Biochem > Flashcards

Biochem Flashcards

1
Q

Phosphofuctokinase-1

A

RL step in glycolysis

Upregulators: AMP, fructose-2,6-bisphosphae

Downregulators: ATP, citrate

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

Fructose-1,6-bisphosphatse

A

RL step in gluconeogenesis; occurs at same location as PFK-1 in glycolysis

Up: ATP, acetyl-CoA

Down: AMP, fructose-2,6-bisphosphatase

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

Glycolysis steps that produce ATP

A

Phosphoglycerate kinase

Pyruvate kinase

Up: Fructose-1,6-bisphosphate

Down: ATP, alanine

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

Phosphofructokinase-2

A

Forms fructose-2,6-bisphosphate from F6P

-This product upregulates glycolysis

Up: Phosphorylation (caused by glucagon =» increased cAMP =» increased PKA)

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

Ketogenic diet

A

Needed for babies/pts. w/ pyruvate dehydrogenase deficiency; pts. get a buildup of lactate and alanine

Clinical: Neurologic deficits, lactic acidosis, increased alanine

Tx: Increased leucine and lysine in diet (ketogenic AAs) or high fat diet

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

Interference w/ Complex IV of the ETC

A

CN-; CO

-Decreases proton gradient and blocks ATP synthesis

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

Brown fat

A

Produces thermogenin which is an ETC uncoupler (decreases proton gradient)

  • Produces heat
  • Dinitrophenol (used for weight loss) and aspirin (fever w/ OD) also produce this effect
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Classic galactosemia

A

Galactose-1-phosphate uridyltransferase deficiency

Clinical: Failure to thrive, jaundice, hepatomegaly, infantile cataracts, intellectual disability

-Galactokinase deficiency presents as a milder version with only signs being reducing sugar in urine and faint cataracts

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

Aldose reductase

A

Converts glucose to sorbitol

Is a problem in cells with constitutive glucose uptake like retinal cells and the kidney

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Carbamoyl phosphate synthetase I

A

Converts NH4+ to carbamoyl phosphate

-Reacts with Ornithine in the mitochondria to make citrulline

⭐️Enzyme requires n-acetylglutamate

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

Two options for Pyruvate under hypoxic conditions

A

Converted to lactate or alanine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Hyperammonemia Tx (3 things)

A

Rifaximin - decreases colonic ammoniagenic bacteria

Lactulose - traps NH4

Avoid protein in diet

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

Increased Orotic acid in urine BUT no Megaloblastic anemia

A

Ornithine Transcarbomylase deficiency; since Citrulline can’t be formed, carbamoyl phosphate is broken down to orotic acid

Presents in first few days of life as ammonia intoxication

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

️Enzyme deficiency in albinism

A

Tyrosinase

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

Musty body Oder

A

PKU; disorder of aromatic AA metabolism leading to toxic buildup, also possibly due to BH4 deficiency

Clinical: Intellectual disability
Growth retardation
Seizures
Eczema, fair skin

Tx: Avoid Phe in diet (artificial sweeteners), supplement tyrosine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

(+) urinary cyanide-Nitroprusside test

A

Cystinuria

-Renal PCT inability to reabsorb cysteine, Ornithine, lysine, and arginine (COLA)

Tx: urinary alkalinization, Acetazolamide, hydration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Glucose-6-phosphatase deficiency

A

Von-Gierke’s Disease; pts. must avoid fructose and galactose

Clinical: Severe fasting hypoglycemia, increased glycogen, increased lactic acid, increased uric acid, increase triglycerides, hepatomegaly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Lysosomal a-1,4-glucosidase deficiency

“Acid maltase”

A

Pompe disease

Clinical: Cardiomegaly, hypertrophic cardiomyopathy, exercise intolerance

*AT RISK FOR EARLY DEATH

19
Q

a-1,6-glucosidase deficiency

A

Cori Disease; gluconeogenesis intact but pts. can’t debranch glycogen

Clinical: Mild hypoglycemia, mild hepatomegaly, mild uric acidemia, normal lactic acid

20
Q

Glycogen phosphorylase deficiency

A

Mcardle’s Disease

Clinical: Exercise intolerance (muscle cramps), myoglobinuria, electrolyte abnormalities

Tx: Vit B6

21
Q

a-galactosidase A deficiency

A

Fabry disease

Clinical: Peripheral neuropathy of hands and feet, angiokeratomas, CVD

  • Increased ceramide trihexoside
  • XLR inheritance***
22
Q

Glucocerebrosidase deficiency

A

Gaucher’s Disease; causes accumulation of glucocerebroside

Clinical: Hepatosplenomegaly, pancytopenia, aseptic necrosis off fthe femur

*Chicken-scratch monos

23
Q

Sphingomyelinase deficiency

A

Niemann-Pick Disease; accumulation of sphingomyelin

Clinical: Progressive neurodegeneration, HEPATOSPLENOMEGALY (as opposed to?), foam cells, cherry-red macula

24
Q

Hexosaminidase A deficiency

A

Tay-Sach’s Disease; accumulation of GM2 ganglioside

Clinical: Progressive neurodegeneration, cherry-red macula, developmental delay

25
Q

Galactocerebrocidase deficiency

A

Krabbe’s disease; accumulation of galactocerebroside

Clinical: Peripheral neuropathy, developmental delay, optic atrophy, globoid cells

26
Q

Arylsulfatase A deficiency

A

Metachromatic leukodystrophy; accumulation of cerebroside sulfate

Clinical: Ataxia, dementia (due to demyelination of CNS and PNS)

27
Q

a-L-iduronidase deficiency

A

Hurler Syndrome; accumulation of heparan and dermatan sulfate (mucopolysaccharides)

Clinical: Developmental delay, gargoylism (coarse facial features), corneal clouding (as opposed to), hepatosplenomegaly

28
Q

Iduronate sulfatase deficiency

A

Hunter Syndrome; accumulation of heparan and dermatan sulfate (mucopolysaccharides)

Clinical: Mild hurlers + AGGRESSIVENESS
*Hunters see clearly and angrily aim for the X”

XLR inheritance

29
Q

Medium-chain acyl-CoA dehydrogenase deficiency

A

Inability to break down theses FAs; presents as hypoketotic hypoglycemia w/ seizures, coma

AVOID FASTING STATES

-Similar to carnitine deficiency BUT carnitine is LCFAs (why?)

30
Q

Lipoprotein Lipase deficiency

A

Familial hyperchlomicronemia; increased serum chylomicrons, TG, and cholesterol

Clinical: Pancreatitis, hepatosplenomegaly, pruritic xanthomas

***Creamy layer in supernatant

31
Q

Defective LDL receptors

A

Familial hypercholesterolemia; increased serum LDL and cholesterol

Clinical: Accelerated atherosclerosis (MI prior to 20 possible), tendonous xanthomas, corneal arcus (white ring on the periphery of the iris)***

32
Q

Hepatic overproduction of VLDL

A

Hypertriglyceridemia; increased serum VLDL and TGLs

Clinical: Acute pancreatitis; serum TGL increase

AD inheritance*

33
Q

Chlordiazepoxide

A

Benzodiazepine

34
Q

Clomipramine

A

TCA that can successfully treat OCD in children and adults

35
Q

TGF-B receptor

A

Receptor serine/threonine kinase

36
Q

Long term dialysis complication

A

Amyloidosis consisting of B2-microglobulin

37
Q

Increased Rhine hydroxyproline

A

Indicates increased bone resorption by osteoclasts

38
Q

Bone repair

A
  1. Ruptured blood vessels form a hematoma bridging the fracture gap
  2. (1 week) Soft tissue callus anchors the fracture
  3. Osetoblasts deposit immature woven bone
    • will see irregularly arranged collagen
  4. Hyaline cartilage forms at periphery and undergoes endochondral ossification
    ⭐️”bony callus”
  5. Bony callus turns to mature lamellar bone
39
Q

Areas with no BBB

A

Median eminence, area postrema, choroid plexus, pineal gland, neurohypophysis

40
Q

Phase I Reactions

A

Include oxidation, desulfuration, epoxide formation, hydoxylation

Monoamine oxidase can locally hydrolyze some drugs as well

41
Q

Chenocholic acid/ Cholic acid

A

First product formed in production of bile salts; these are increased alongside bile salts w/ increased prod.

42
Q

Hepatic Stellate Cells

A

Found in the perisinusoidal space (space of Disse) and secrete type I collagen

***Very important in hepatic scarring and portal HTN

43
Q

General concepts of hepatic zone necrosis

A

Zone 1 =» Few toxins, chronic hepatitis

Zone 2 =» Yellow fever

Zone 3 =» Ischemia, Right-sided HF, CCl4, amantin, copper, acetominophen (go to guess)

44
Q

Microvesicular steatosis causes

A

Tetracycline, VA

STEP (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions