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Flashcards in 560D Deck (125)
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1

Which of the following factors can increase likelihood of getting Iron def. Anemia?

a. All of these responses can increase the risk of getting IDA
b. Heavy menstruation
c. Celiac disease
d. Deficiency of Copper

A) All of these responses can increase the risk of getting IDA

2

2. Anemia of chronic disease can be caused from prolonged inflammation (IL-6, Cytokines, infection), which increases level of _____________ to sequester iron in tissues so germs can't use the iron to reproduce.

a. Hepcidin (synthesized by the liver and controls iron homeostasis)
b. Aconitase
c. B-12
d. Folic Acid

a. Hepcidin (synthesized by the liver and controls iron homeostasis)

3

3. What are the four conditionally essential amino acids?

a. Arg, Gln, Gly, Tau
b. Arg, Gln, Gly, Ser
c. Arg, Glu, Gly, Tau
d. Arg, Glu, Gly, Ser

a. Arg, Gln, Gly, Tau

4

4. Mutations in the SN1-SN2 transporter can lead to elevations in what 3 AA?

a. Gln, Asn, His
b. Glu, Asn, His
c. Glu, Asp, His
d. Gln, Asp, His

a. Gln, Asn, His

5

5. The central energy pathways begin with digestion and assimilation of fats, carbohydrates, and proteins. Long chain FA require the use of the _________________ shuttle to help them enter the mitochondrial for beta-oxidation.

a. Carnitine
b. Malate
c. Aspartate
d. Carnosine

a. Carnitine

6

6. Inhibition of CoQ10 synthesis from statin drugs, will typically reveal elevations in urinary_____________________.

a. Hydroxymethylglutarate
b. Hydroxymethylbutyrate
c. Hydroxymethylpropionate
d. Hydroxymethylsuccinate

a. Hydroxymethylglutarate

7

7. When considering toxic exposures, through what barriers and routes of entry can lipophilic (fat loving) toxins be absorbed?

a. All of these responses
b. Through the GI tract
c. Through the skin
d. Through the lymphatics
e. In utero

a. All of these responses

8

8. One of the phthalate esters used in plastic wrap to cover foods can lead to decreased kidney function, increased cysts, increased peroxisome proliferation and even liver cancer in rats. This is a concern to humans because ________________ is used in plastic tubing for hemodialysis.

a. Di(2-ethylhexyl) phthalate (DEHP)
b. Dimethyl phthalate (DMP)
c. Diethyl phthalate (DEP)
d. Polyethylene terephthalate (PETE

a. Di(2-ethylhexyl) phthalate (DEHP)

9

- A client with diagnosed IDA comes to you because he eats meat-based protein and green leafy vegetables but his iron levels have not increased. What other nutrient is needed to properly absorb iron?

- Vitamin C
- B-12
- Folic Acid
- Intrinsic Factor

Vitamin C

10

- Which of the following factors increase likelihood of getting IDA?

- All of these responses can increase the risk of getting IDA
- Heavy menstruation
- Celiac Disease
- Deficiency of Copper

All of these responses can increase the risk of getting IDA

11

- It is important to differentiate IDA from Thalassemia because…

- Blood transfusion in Thalassemia can lead to iron overload
- ID can cause Thalassemia
- ID can cause hemolytic anemia
- Thalassemia can cause Iron Deficiency

Blood transfusion in Thalassemia can lead to iron overload

12

- Sideroblastic anemia is an X-linked condition where the enzyme called __________ is mutated, leading to excess iron in the RBC mitochondria.

- Delta-aminolevulinic acid synthase (this is also the enzyme that controls the rate limiting step in heme synthesis)
- Protoporphyrin IX oxidase
- NADH methemoglobin reductase
- Diaphorase I

Delta-aminolevulinic acid synthase (this is also the enzyme that controls the rate limiting step in heme synthesis)

13

- Glucose-6-Phosphate dehydrogenase is the enzyme that reduces (A) to (B) as part of the hexose monophosphate shunt pathway (pentose phosphate pathway. G6PD deficiency can lead to RBC hemolysis from oxidant stress because (B) is no longer available to help recycle glutathione.

- (A) NADP+, (B) NADPH
- (A) NADPH, (B) NADP+
- (A) NAD+, (B) NADH
- (A) NADH, (B) NAD+

(A) NADP+, (B) NADPH

14

- What symptoms if Iron Deficiency Anemia block hepcidin expression, leading to increased ferroportin and iron availability?

- Hypoxia and Erythropoiesis
- Fatigue and dizziness
- Pale skin and weakness
- Low blood pressure and palpitations

Hypoxia and Erythropoiesis

15

- Methemoglobin differs from hemoglobin by its inability to bind to oxygen because:

- The iron has been oxidized to Fe3+
- The iron has been reduced to Fe2+
- It has a zinc bound instead of an iron molecule
- It has a cobalt bound to it instead of an iron molecule

The iron has been oxidized to Fe3+

16

- It is important to simultaneously check vitamin B12 and folate levels because administration of folic acid can mask vitamin B12 deficiency, leading to neurological demyelination that is often irreparable. The 2 constituents that accumulate in B12 deficiency, one of which competitively inhibits FA biosynthesis leading to increased myelin sheath turnover/degradation are:

- Methylmalonyl Coa and homocysteine
- Succinyl CoA and homocysteine
- Acetyl CoA and homocysteine
- Succinyl CoA and Methylmalonyl CoA

Methylmalonyl Coa and homocysteine

17

- A client with diagnosed pernicious anemia does not have the ability to produce intrinsic factor. What nutrient binds to intrinsic factor to be properly absorbed and where is it absorbed in the GI tract?

- Vitamin B12, Ileum
- Folic Acid, Ileum
- Iron, Duodenum
- Vitamin B12, Duodenum

b12, ileum

18

- GI conjugase enzymes hydrolyze folate to the monoglutamate form. What cofactor is needed for this reaction?

- Zinc
- Magnesium
- Copper
- Vitamin C

Zinc

19

- Vitamin B12 is composed of ___________________, which can have hydroxy-, methyl-, or deoxyadenosyl- groups attached to it.

- Corrin ring with cobalt
- Corrin ring with iron
- Corrin ring with Zinc
- Corrin ring with magnesium

Corrin ring with cobalt

20

- The reabsorption of urobilinogens from the GI to the liver so they can be resecreted into the bile is called
the _________________.

- Enterohepatic Urobilinogen cycle
- Enterosplenic Urobillinogen Cycle
- Hepatosplenic Urobillinogen cycle
- Enterohepatic Stercobillin cycle

Enterohepatic Urobilinogen cycle

21

- How can porphyrias arise from a low caloric (low glucose) diet

- Because ALA synthase 1 will be upregulated to puse heme biosynthesis (Glucose inhibits ALAS1, so it is automatically upregulated in the absence of glucose. This is why glucose is given IV to people with acute porphyrias and why it is important for people with porphyrias to avoid crash dieting and low-carb diets).
- Because ALAS1 will be downregulated to push the heme biosynthesis pathway
- Because Delta-ALA dehydratase will be upregulated in the heme biosynthesis pathway
- Because Delta-ALA dehydratase will be downregulated in the heme biosynthesis pathway

Because ALA synthase 1 will be upregulated to puse heme biosynthesis (Glucose inhibits ALAS1, so it is automatically upregulated in the absence of glucose. This is why glucose is given IV to people with acute porphyrias and why it is important for people with porphyrias to avoid crash dieting and low-carb diets).

22

- Obstruction of the bile duct from gallstones (called extrahepatic cholestasis) can cause symptoms of pale clay colored stools and dark urine upon standing. This occurs because:

- The liver regurgitates conjugated bilirubin into the blood and the decline of conjugated bilirubin entering the GI tract
- The liver regurgitates unconjugated bilirubin in the blood and the decline of unconjugated bilirubin entering the GI tract
- The liver regurgitates stercobilin into the blood and the decline of urobilinogen entering the GI tract
- The liver regurgitates biliverdin into the blood and the decline of heme entering the GI tract


- The liver regurgitates conjugated bilirubin into the blood and the decline of conjugated bilirubin entering the GI tract

23

- Hyperbilirubinemia can lead to Jaundice, yellowing of the skin, nail beds and whites of the eyes. Acute hemolytic crises found in G6PD deficiency and Sickle Cell Anemia can cause hyperbilirubinemia and jaundice from an:

- Increase in unconjugated and conjugated bilirubin
- Increase in unconjugated bilirubin only
- Increase in conjugated bilirubin only
- Increase in stercobilin and urobilinogen

Increase in unconjugated and conjugated bilirubin

24

- Which enzyme in the heme biosynthesis pathways contains zinc and is located in the cytosol?

- Hydroxymethylbilane synthase
- Uroporphyrinogen Decarboxylase
- Delta-ALA-Dehydratase (this enzyme converts 2 ALA into porphobilinogen and is very sensitive to heavy metals like lead because they replace the zinc)
- ALA synthase

Delta-ALA-Dehydratase (this enzyme converts 2 ALA into porphobilinogen and is very sensitive to heavy metals like lead because they replace the zinc)

25

- How is a porphyrin different from a porphyrinogen?

- Porphyrins are functional intermediates of heme synthesis
- Porphyrins are reduced forms of porphyrinogens
- Porphyrins are the colorless form of porphyrinogens
- Porphyrins are oxidized forms of porphyrinogens

- Porphyrins are oxidized forms of porphyrinogens

26

- During heme degradation, which degradation product of bilirubin gives urine its yellow color?

- Urobilin
- Stercobilin
- Bilirubin diglucuronide

Urobilin

27

- Alanine aminotransferase converts alpha-ketoglutarate into glutamate and alanine into:


- Aspartate
- Pyruvate
- Oxaloacetate
- Glutamate

Pyruvate

28

- What cofactor assists aminotransferases like ALT and AST in their ability to transfer amino groups?

- Pyridoxamine Phosphate
- Vitamin B5
- P5P
- Vitamin C

Pyridoxal-5-Phosphate (Pyridoxal-5-Phosphate (B6) is required by all aminotransferases, actually holds onto the amino group that get transferred during the enzymatic process, and gets recycled for continual use of these reactions).

29

- Gamma-glutamyl transpeptidase (GGT) is responsible for breaking down (A) into (B)

- (A) GSH, (B) Gamma-glutamylAA + Cysteinylglycine
- (A) GSH, (B) Gamma-glutamylAA + Cysteineglutamate
- (A) GSH, (B) Gamma-glutamylAA + Cysteineglutamine
- (A) GSH, (B) Gamma-glutamylAA + Cysteineloxoproline

(A) GSH, (B) Gamma-glutamylAA + Cysteinylglycine

30

- How many ATP are utilized in the gamma-glutamyl cycle to resynthesize glutathione?

- 4 ATP
- 3 ATP
- 1 ATP
- 2 ATP

3 ATP