Z Biochemistry -- Misc

Front 1

A deficiency of vitamin B6 is inducible by what two drugs?

Back 1

Isoniazid and oral contraceptive pills

Front 2

What is the most common vitamin deficiency in the United States?

Back 2

Folic acid deficiency

Front 3

A deficiency of vitamin B3 (niacin) leads to what disease?

Back 3

Pellagra

Front 4

A patient presents with hemolytic anemia, muscle weakness, and neuropathy; what vitamin deficiency do you suspect?

Back 4

Vitamin E

Front 5

A deficiency of _____ may be caused by the use of antibiotics or the ingestion of raw eggs

Back 5

Biotin

Front 6

Supplemental folic acid is given during early pregnancy to reduce the incidence of _____ _____ _____.

Back 6

Neural tube defects

Front 7

Name two topical uses of vitamin A.

Back 7

It can be used topically for wrinkles and for acne

Front 8

A patient being treated for hyperlipidemia complains of becoming red in the face after taking his medication; what drug is he taking

Back 8

He is likely on niacin, which at pharmacologic doses can cause facial flushing

Front 9

Is accumulation of fat- or water-soluble vitamins more likely to cause toxicity?

Back 9

Fat

Front 10

Calcium homeostasis is associated with which fat-soluble vitamin?

Back 10

Vitamin D

Front 11

Why are the brain and heart susceptible to injury in thiamine deficiency?

Back 11

Cells cannot generate adenosine triphosphate without thiamine and highly metabolically active cells are damaged first

Front 12

What is another name for vitamin B5?

Back 12

Pantothenate

Front 13

Which vitamin is needed for the conversion of methylmalonyl-CoA to succinyl-CoA?

Back 13

Vitamin B12 (cobalamin)

Front 14

What dietary deficiency can exacerbate alcoholic cirrhosis?

Back 14

Zinc

Front 15

Is vitamin D2 found in plants or produced in sun-exposed skin?

Back 15

Vitamin D2 is found in plants

Front 16

Are the B-complex vitamins fat soluble or water soluble?

Back 16

Water soluble

Front 17

Are pyridoxine, pyridoxal, and pyridoxamine fat soluble or water soluble?

Back 17

Water soluble

Front 18

A patient has swollen gums, bruising, anemia, and poor wound healing. What vitamin deficiency is probably responsible for these symptoms?

Back 18

Vitamin C deficiency

Front 19

True or False? Eating excess untreated corn can lead to pellagra.

Back 19

True; vitamin B3 in corn is not absorbable unless treated

Front 20

What form of vitamin D is found in vitamins and other pharmaceuticals?

Back 20

Vitamin D2

Front 21

S-adenosylmethionine is formed from what two precursors?

Back 21

Adenosine triphosphate and methionine

Front 22

True or False? The neurologic sequelae of vitamin B12 deficiency are easily reversible with vitamin supplementation.

Back 22

False; a prolonged deficiency of cobalamin leads to irreversible nervous system damage

Front 23

What is the pathophysiology of the neurologic signs and symptoms of B12 deficiency?

Back 23

Synthesis of abnormal myelin

Front 24

Which water-soluble vitamin is associated with collagen synthesis?

Back 24

Vitamin C (ascorbic acid)

Front 25

Which clotting factors are dependent on vitamin K?

Back 25

Factors II, VII, IX, and X and proteins C and S

Front 26

What are the signs and symptoms of vitamin A deficiency?

Back 26

Night blindness and dry skin

Front 27

What is another name for vitamin D3?

Back 27

Cholecalciferol

Front 28

A malnourished child is also anemic, edematous, and has elevated liver function tests; what is the diagnosis?

Back 28

Kwashiorkor (remember: Kwashiorkor results from a protein-deficient MEAL: Malnutrition, Edema, Anemia, Liver (fatty))

Front 29

A deficiency of vitamin D causes what disease in children?

Back 29

Rickets

Front 30

How can Hartnup disease lead to pellagra

Back 30

Through impaired absorption of tryptophan, which is used to synthesize niacin

Front 31

Which step in glycolysis requires thiamine

Back 31

Thiamine pyrophosphate is needed as a cofactor for pyruvate dehydrogenase

Front 32

Ethanol ingestion leads to the increased conversion of pyruvate to _____ and oxaloacetate to _____, because these reactions regenerate NAD+ from NADH.

Back 32

Lactate; malate

Front 33

Wernicke-Korsakoff syndrome is caused by a deficiency of which vitamin?

Back 33

Vitamin B1 (thiamine)

Front 34

Is vitamin C fat soluble or water soluble?

Back 34

Water soluble

Front 35

Vitamin B1 is the precursor to what metabolic cofactor?

Back 35

Thiamine pyrophosphate

Front 36

True or False? In addition to diarrhea, dermatitis, and dementia, pellagra is also characterized by beefy glossitis.

Back 36

TRUE

Front 37

How can malignant carcinoid syndrome lead to pellagra?

Back 37

Through increased metabolism of tryptophan, which is used to synthesize niacin

Front 38

The high NADH/NAD+ ratio seen after ethanol ingestion is responsible for the shunting of metabolites away from _____ and toward _____ _____ synthesis.

Back 38

Gluconeogenesis; fatty acid

Front 39

A 42-year-old woman with a history of gastric bypass surgery 5 years ago presents with visual disturbance and numbness in her fingers. She is found to have macrocytic anemia. What is the most likely cause of her symptoms?

Back 39

Vitamin B12 deficiency

Front 40

What is the cause of hemorrhagic disease of the newborn? How is it prevented?

Back 40

The neonatal intestine is sterile and therefore cannot synthesize vitamin K; to prevent hemorrhage, all newborns are given a vitamin K injection at birth

Front 41

True or False? Vitamin C is required for the conversion of dopamine to norepinephrine

Back 41

TRUE

Front 42

What enzyme uses S-adenosylmethionine to create homocysteine from methionine?

Back 42

Homocysteine methyltransferase

Front 43

A patient taking fomepizole would have a decreased accumulation of _____ because it inhibits _____.

Back 43

Acetaldehyde; alcohol dehydrogenase; fomepizole is used in cases of methanol poisoning

Front 44

Vitamin K deficiency leads to _____ (increased/decreased/normal) prothrombin time, _____ (increased/decreased/normal) activated partial thromboplastin time, and _____ (increased/decreased/normal) bleeding time.

Back 44

Increased, increased, normal (remember: K for Koagulation)

Front 45

Which groups of vitamins are water soluble

Back 45

B vitamins and vitamin C

Front 46

In which organ is folate stored?

Back 46

The liver

Front 47

What is another name for vitamin C?

Back 47

Ascorbic acid

Front 48

Biotin and pyruvate carboxylase catalyze what reaction?

Back 48

Conversion of pyruvate to oxaloacetate

Front 49

What is another name for vitamin B2?

Back 49

Riboflavin

Front 50

Vitamin C _____ (promotes/inhibits) iron absorption by keeping it in the _____ (reduced/oxidized) state, which is more absorbable.

Back 50

Promotes; reduced

Front 51

What is the importance of zinc fingers?

Back 51

Zinc fingers allow transcription factors and other molecules to interact with DNA

Front 52

What are dietary sources of vitamin B12?

Back 52

Animal products

Front 53

Which fat-soluble vitamin acts as an antioxidant?

Back 53

Vitamin E

Front 54

Where in the cell is the reaction that is inhibited by disulfiram?

Back 54

Disulfiram inhibits acetaldehyde dehydrogenase, which is in the mitochondria

Front 55

What is the storage form of vitamin D?

Back 55

25-OH D3

Front 56

What is another name for vitamin D2?

Back 56

Ergocalciferol

Front 57

Marasmus is the result of a deficiency of _____ in the diet.

Back 57

Calories

Front 58

Biotin is bound by _____, which is found in egg whites.

Back 58

Avidin (remember: AVID in egg whites AVIDly binds biotin)

Front 59

What are the symptoms associated with vitamin A intoxication?

Back 59

Arthralgias, fatigue, headaches, skin changes, sore throat, and alopecia

Front 60

A deficiency of vitamin D may lead to ______ (hypocalcemia/hypercalcemia) and ______ (flaccid paralysis/tetany).

Back 60

Hypocalcemia; tetany

Front 61

A patient has delayed wound healing, hypogonadism, and decreased axillary, facial, and pubic hair. What nutritional deficiency is likely to be responsible for these symptoms

Back 61

Zinc deficiency

Front 62

What are dietary sources of vitamin C?

Back 62

Fruits and vegetables; British sailors carried limes to prevent scurvy (origin of the word "limey")

Front 63

Ethanol metabolism _____ (increases/decreases) the NADH/NAD+ ratio in the liver, which _____ (promotes/inhibits) gluconeogenesis.

Back 63

Increases; inhibits

Front 64

Deficiency of which two water-soluble vitamins can cause macrocytic anemia?

Back 64

Folate and B12

Front 65

What is the effect of vitamin D on your bones

Back 65

Vitamin D increases bone resorption

Front 66

What foods contain high amounts of vitamin A?

Back 66

Vitamin A is found in liver, and in leafy vegetables

Front 67

A patient has hypercalcemia, loss of appetite, and stupor. What vitamin excess is probably responsible for these symptoms?

Back 67

Vitamin D

Front 68

Which vitamin is required for the synthesis of niacin from tryptophan?

Back 68

Vitamin B6 (pyridoxine)

Front 69

What is another name for vitamin B3?

Back 69

Niacin

Front 70

What vitamin is a component of fatty acid synthase?

Back 70

Vitamin B5 (pantothenate)

Front 71

What vitamin is the precursor of oxidized nicotinamide adenine dinucleotide and oxidized nicotinamide adenine dinucleotide phosphate?

Back 71

Vitamin B3 (niacin) (remember: NAD derived from Niacin, B3 = 3 ATP)

Front 72

A deficiency of vitamin D causes what disease in adults?

Back 72

Osteomalacia

Front 73

What by-product of ethanol metabolism is responsible for hepatic steatosis?

Back 73

The accumulation of NADH drives pyruvate to lactate and oxaloacetate to malate, resulting in decreased gluconeogenesis and increased fatty acid synthesis

Front 74

What test is used to detect the cause of a deficiency of vitamin B12?

Back 74

The Schilling test

Front 75

A child presents with tissue and muscle wasting with loss of subcutaneous fat. Is she more likely to have kwashiorkor or marasmus

Back 75

Marasmus

Front 76

What is the clinical picture of a patient with kwashiorkor?

Back 76

Small child with swollen belly

Front 77

Why are alcoholics prone to beriberi and Wernicke-Korsakoff syndrome?

Back 77

Malnutrition and malabsorption

Front 78

What is cheilosis?

Back 78

Inflammation of the lips, with scaling and fissures at the corners of the mouth; this is seen in vitamin B2 deficiency

Front 79

Vitamin C is needed for the addition of _____ groups to the amino acids lysine and proline during collagen synthesis.

Back 79

Hydroxyl

Front 80

Adrenal insufficiency may be caused by a deficiency of which vitamin?

Back 80

Vitamin B5 (pantothenate)

Front 81

A known alcoholic presents with symptoms of muscle wasting and polyneuritis. What vitamin deficiency do you suspect?

Back 81

Vitamin B1 (thiamine)

Front 82

Cheilosis and corneal vascularization occur as a result of a deficiency of which vitamin?

Back 82

Vitamin B2 (riboflavin) (remember: the 2 C's)

Front 83

What are dietary sources of folate?

Back 83

Leafy greens (remember: FOLate from FOLiage)

Front 84

Is pantothenic acid fat soluble or water soluble?

Back 84

Water soluble

Front 85

What is the functional group involved in S-adenosylmethionine reactions?

Back 85

S-adenosylmethionine tranfers methyl units (remember: S-adenosylmethionine the methyl donor man)

Front 86

Where in the cell is the reaction that is inhibited by fomepizole?

Back 86

Fomepizole blocks the action of alcohol dehydrogenase, which is in the cytosol

Front 87

What happens to the rate of ethanol metabolism by alcohol dehydrogenase as more ethanol is consumed?

Back 87

There is no change in the rate since this reaction proceeds by zero-order kinetics

Front 88

What are the "3 D's" of pellagra?

Back 88

Diarrhea, Dermatitis, and Dementia

Front 89

Which vitamin is the precursor to pyridoxal phosphate?

Back 89

Vitamin B6 (pyridoxine)

Front 90

Is thiamine fat soluble or water soluble?

Back 90

Water soluble

Front 91

All of the water-soluble vitamins easily wash out from the body, except for which two?

Back 91

Vitamin B12 and folate

Front 92

What enzyme does disulfiram inhibit?

Back 92

Acetaldehyde dehydrogenase

Front 93

What enzyme requires a biotin cofactor to create oxaloacetate?

Back 93

Pyruvate carboxylase

Front 94

What are the symptoms of zinc deficiency

Back 94

Delayed wound healing; hypogonadism; decreased adult hair in the axilla, face, and pubic regions; dysgeusia; anosmia

Front 95

What disease is caused by a deficiency of vitamin C?

Back 95

Scurvy

Front 96

What are the neurologic manifestations of vitamin B12 deficiency?

Back 96

Subacute combined degeneration, paresthesia, and optic neuropathy

Front 97

What is another name for vitamin B1?

Back 97

Thiamine

Front 98

Are polyneuritis and muscle wasting characteristic of wet or dry beriberi?

Back 98

Dry beriberi; wet beriberi is associated with high-output cardiac failure and edema

Front 99

What is the mechanism by which antibiotic use can cause vitamin K deficiency?

Back 99

Destruction of intestinal bacteria, which synthesize vitamin K

Front 100

What are the symptoms of vitamin B5 deficiency?

Back 100

Dermatitis, enteritis, alopecia, and adrenal insufficiency

Front 101

What are the results of folate deficiency?

Back 101

Macrocytic and megaloblastic anemias

Front 102

Clotting factor synthesis depends on which fat-soluble vitamin?

Back 102

Vitamin K

Front 103

What is the role of thiamine in the tricarboxylic acid cycle?

Back 103

It is a cofactor for α-ketoglutarate dehydrogenase

Front 104

When drinking a glass of milk, what type of vitamin D are you absorbing?

Back 104

Vitamin D3 (remember: drinking milk (fortified with vitamin D) is good for bones)

Front 105

Which vitamin is needed as a cofactor for glycogen phosphorylase?

Back 105

Vitamin B6 (pyridoxine)

Front 106

In what disease do epithelioid macrophages convert vitamin D into its active form in excess, leading to hypercalcemia?

Back 106

Sarcoidosis

Front 107

What vitamin is required for conversion of tryptophan to niacin?

Back 107

Vitamin B6 (pyridoxine)

Front 108

Kwashiorkor is a deficiency of _____ that results in skin lesions, anemia, edema, and liver malfunction (fatty change). By contrast, marasmus is a deficiency of _____ that results in tissue wasting.

Back 108

Protein; calories

Front 109

What are the clinical features of vitamin B6 deficiency?

Back 109

Convulsions, hyperirritability, peripheral neuropathy, and sideroblastic anemias

Front 110

What form of folate acts as a metabolic cofactor?

Back 110

Tetrahydrofolate

Front 111

Vitamin D increases the absorption of what two ions in the intestine?

Back 111

Calcium and phosphorus

Front 112

What are the hematologic manifestations of vitamin B12 deficiency?

Back 112

Megaloblastic anemia