2nd Sem - 7th Evals Batch 2018 Flashcards
1
Q
- Which of the following is NOT a component of HEME? a. Pyrrole rings
• holds the N2 ion at the center part b. Methyl side chains
• methyl side chains together with vinyl and and proprionate c. Ferrous ions
• heme is an iron containing porphyrin in its FERROUS (Fe2+) state d. Ferric ions
• only ferrous (Fe2+) not Fe3+
A
D
2
Q
- Which of the following statement is TRUE of heme synthesis in in man?
a. delta-aminolevulinic acid is formed by the condensation of succinyl CoA and
valine.
• succinyl-CoA and Glycine not Valine
b. uroporphyrin III is the immediate precursor of coproporhyrin III • uroporphyrinogen not uropophyrin
c. porphobilinogen is formed by the condensation of two delta-aminolevulinic d. ferric iron is inserted into protoporphyrin IX prior to attachment to the globin
molecule
• ferrous ion not ferric
A
C
3
Q
- The rate-limiting step in the synthesis of heme is catalysed by which of the following enzymes?
a. ALA synthase
• first step of heme metabolism
b. ALA dehydratase
• 2nd step of the pathway
c. Uroporphyrinogen synthase
• 3rd step of the pathway
d. Ferrochelatase
• last step of the pathway
A
A
4
Q
- The following are ALL mitochondrial enzymes needed for the synthesis of heme, except which one?
a. ALA synthase
• 1st step happens in mitochondria
b. ALA dehydratase
• 2nd step which happens in the cytosol
c. Protoporphyrinogen oxidase
• 2nd to the last step happens in mitochondria
d. Ferrochelatase
• last step of the pathway happens in mitochondria
A
B
5
Q
- A 4-yr-old boy is brought to the emergency room with abdominal pain, mental status changes, and fatigue. The patient lives with his grandparents in a very old house and he has been sucking on the paint chips that have crumbled in the windowsills.This made the

doctor suspect lead poisoning.Lead typically interferes with an enzyme that causes accumulation of which of the following?
The steps catalysed by ferrochelatase and ALA Dehydrase are inhibited by lead.
a. Porphobilinogen
• substrate of Uropophyrinogen synthese which not inhibited by lead
b. Protoporphyrin IX
• can also be the answer but since this is included in the last step, lead
usually inhibits ALA Dehydrase first c. Aminolevulinic acid
• substrate of ALA Dehydrase which is the 2nd step of the pathway d. Uroporphyrinogen
• enzyme utilizing this is not inhibited by lead which are Uroporphyrinogen I synthase & Uroporphyrinogen III cosynthase
A
C
6
Q
- Which of the following statements is TRUE of the regulation of heme synthesis? a. Heme inhibits the synthesis of ALA synthase.
• feedback inhibition/repression mechanism
b. The steps catalysed by ferrochelatase and ALA Dehydrase are inhibited by lead
• stated in #5
c. Drugs like phenobarbital induce heme synthesis by activating ALA synthase
• yup, examples of which are anti-epileptic drugs d. All of the above
A
D
7
Q
- An 18-yr-old woman who recently began taking birth control pills presents to the emergency room with cramping abdominal pain, anxiety, paranoia, and hallucinations. A surgical evaluation, including ultrasound and CT scan, fail to demonstrate an acute abdominal process. Her urine gets darkened on exposure to light and urinalysis reveals an increase in urine porphyrins. Which of the following is the most likely?
a. Congenital erythropoietic porphyria
• Erythropoietic porphyria patients have photosensitive skin causing
photodermatitis in this case the patient is not photosensitive b. Acute intermittent porphyria
• Deficiency of the enzyme uroporphyrinogen I synthase; increased excretion of porphyrin precursors like porphobilinogen and d- aminolevulinate (ALA). Patient’s urine with this kind of porphyria gets dark when exposed to air
c. Erythropoietic protoporphyria
• Erythropoietic porphyria patients have photosensitive skin causing
photodermatitis in this case the patient is not photosensitive d. Porphyria cutanea tarda
• deficient in the enzyme activity of uroporphyrinogen decarboxylase
A
B
8
Q
8. A 12-yr-old boy sees a dermatologist because he develops vesicles and bullae on his face and arms that appeared after a 3-day trip to Boracay.His father has a similar condition. A  diagnosis of porphyria cutanea tarda is confirmed by finding elevated levels of porphyrins in his serum,urine and stool.His disease is due to deficiency of which of the following enzymes? a. δ- ALA dehydratase • lead poisoning b. Porphobilinogen deaminase • does not cause porphyria c. Porphobilinogen deaminase • does not cause porphyria d. Uroporphyrinogen decarboxylase • causes Porphyria cutanea tarda
A
D
9
Q
- Heme
a. Ferrous Coproporphyrin
is clinically identified as:
• Coproporhyrin is only a precursor b. Ferric Protoporphyrin I
• does not contain Ferric molecule and not 1 but 9 c. Ferrous Protoporphyrin IX
• Ferrous molecule is incorporated in Protoporphyrin by the enzyme ferrocheletase
d. Ferric Uroporphyrin IX
• does not contain ferric molecule
A
C
10
Q
- The following molecules will accumulate in the urine of a patient with lead poisoning,except which one
a. Aminolevulinic acid
• substrate of ALA Dehydrase which is inhibited by lead
b. Protoporphyrins
• substrate of Ferrocheletase which is inhibited by lead
c. Coproporphyrinogens d. Porphobilinogen
• enzyme that uses this is not inhibited by lead
A
D
11
Q
- Which of the following statements is TRUE of heme oxygenase? a. It is the rate-limiting step in the synthesis of heme
• heme oxygenase is for heme degradation
b. It utilizes NADPH and oxygen
c. It cleaves the methenyl bridges of pyrrole rings C and D of the heme
protoporphyrin.
• pyrrole rings A and B, not C and D
d. The ferric iron is reduced and is released as ferrous by this enzyme • ferrous iron (Fe2+) is oxidized to ferric (Fe3+) and released
A
B
12
Q
- A 4-day-old infant develops severe jaundice and is transferred to the neonatal intensive care unit for aggressive phototherapy. He is found to have a complete loss of UDP-GT activity.The loss of this enzyme activity leads to which of the following disorders
a. Crigler – Najjar syndrome
• defective UDP-glucoronyltransferase (Type I= die within 2 years of life;
Type II= less severe defect in bilirubin conjugation)
b. Dubin – Johnson syndrome
• inability to secrete conjugated bilirubin, ↑conjugated bilirubin
c. Gilbert syndrome
• defect in bilirubin uptake, ↑unconjugated bilirubin
d. Rotor syndrome
A
A
13
Q
- Consider the following lab results in a patient who is jaundiced: There is conjugated or unconjugated hyperbilirubinemia, increased urine bilirubin, normal or decreased urine urobilinogen.The above results would be compatible with which of the following diseases?
a. Tumor of the pancreatic head
b. Viral hepatitis
• characteristic of hepatocellular jaundice (hepatic) where there is increased conjugated and unconjugated bilirubin
c. Cholelithiases
• obstructive jaundice (post hepatic), blocked bile duct leads to increased
conjugated bilirubin in the serum d. Hemolytic anemia
• Pre hepatic; increased formation of urobilinogen and stercobilin and urobilin; Elevated unconjugated bilirubin
A
B
14
Q
- The normal brown-red color of feces is due to the presence of: a. Bilirubin
b. Biliverdin
• green bile pigment
c. Urobilin
• responsible for yellow color of urine
d. Stercobilin
A
D
15
Q
- A rise in serum “direct” bilirubin would be expected in:
a. hemolytic jaundice.
• ↑ formation of urobilinogen and stercobilin and urobilin
• ↑ unconjugated bilirubin
b. absence of glucuronyl transferase as in the newborn.
• neonatal physiologic jaundice; ↑ unconjugated bilirubin c. decreased hepatic uptake of bilirubin (Gilbert’s Disease)
• ↑ unconjugated bilirubin d. biliary obstruction.
• ↑ conjugated/direct bilirubin in the serum
A
D
16
Q
- Which of the following statements is/are TRUE regarding the transport of bilirubin to the liver?
a. Bilirubin is transported in the plasma bound to albumin
b. Bilirubin is lipophilic hence it has a tendency to cross the blood brain barrier if
present in massive amounts
c. The protein ligandin will bind to bilirubin once the latter is taken up by the
hepatocytes
d. All of the above
A
D
17
Q
- An otherwise healthy 19-yr-old recovering from a respiratory infection sees his family physician.His examination is unremarkable except for a slight degree of yellow discoloration to his skin and eyes.Laboratory tests are ordered that reveal a mild increase in unconjugated bilirubin but no other abnormalities. Which of the following is the most
likely diagnosis in this patient?
a. Crigler – Najjar syndrome
• defective UDP-glucoronyltransferase, defect in bilirubin conjugation but
children die w/in 2 years of life
b. Erythropoietin deficiency
c. Gilbert syndrome
• defect in bilirubin uptake; ↑unconjugated bilirubin
d. Lead poisoning
• insignificant
A
C
18
Q
- Which of the following laboratory results is that of a patient with haemolytic type of jaundice?
a. Conjugated hyperbilirubinemia, increased urine bilirubin, decreased urine urobilinogen
b. Unconjugated hyperbilirubinemia, decreased /absent urine bilirubin, increased urine urobilinogen
• ↑ formation of urobilinogen and stercobilin and urobilin
• ↑ unconjugated bilirubin
c. Conjugated or unconjugated hyperbilirubinemia, increased urine bilirubin, normal
or decreased urine urobilinogen
d. None of the above
A
B
19
Q
19. The reduction of bilirubin to urobilinogen occurs in: A. LIVER B. LUNGS C. BRAIN D. INTESTINE
A
D
20
Q
- Hemeis synthesized from which of the following compounds?
A. Alanine and propionic acid
B. succinyl CoA and glycine

• delta-aminolevulinic acid is formed by the condensation of succinyl CoA and glycine via ALA synthase.
c. Pyruvate and histidine
d. Oxaloacetate and acetyl CoA
A
B
21
Q
- Calcium in the body fluids is of great importance in which of the following?
a. maintains normal excitability of the heart
b. different aspects of membrane permeability
c. blood coagulation
d. all of the above
A
D
22
Q
- The mineral that is most essential in the synthesis of thyroxine is: a. Potassium
b. Iodine c. Iron
d. Calcium
A
B
23
Q
- Which of the following food is the best source of potassium?
a. Potatoes
• 1570 mg K/100 g (values based on Doc Uy’s ppt- page 9) b. Fresh peas
• 340 mg K/100 g c. Broccoli
• 340 mg K/100 g d. Grapes
• 270 mg K/100 g
A
A
24
Q
- The best source of calcium is:
a. Egg
• 52 mg Ca/L
b. Broccoli
• 100 mg Ca/L
c. human milk
• human colostrum 230 mg Ca/L
• mature human milk 280 mg Ca/L
d. Beef
• 10 mg Ca/L
A
C
25
25. In a patient who is suffering from cholera, the following electrolytes are affected,except which one?
a. sodium
b. magnesium c. bicarbonate d. potassium
B
26
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26. Which of the following is a poor source of iron?

a. chicken meat
b. potato
c. egg
d. white bread
```
D
27
27. The physiologically active form of calcium is:
a. protein-bound
b. complexed
c. ionized
d. Any of the above
C
28
28. The following statements are TRUE of calcium, except which one?
a. Calcium is the most abundant macromineral in the body, majority of which is
mineralized in bone
b. Calcium metabolism is regulated by parathyroid hormone, vitamin D and
calcitonin
c. Calcium deficiency results in scurvy where bones become brittle, and pathologic
fractures result
• Scurvy-Vitamin C deficiency not Calcium
d. Calcium carbonate is the preferred form of supplement 30% of which is absorbed
C
29
29. A deficiency of which of the following definitely causes a disorder?
a. Lead
b. Zinc
c. Mercury d. Cadmium
B
30
30. The mineral that is most essential in the synthesis of thyroxine: a. calcium
b. iron
c. phosphorus d. iodine
D
31
31. Mottling of teeth is a manifestation of excess intake of which of the following minerals? a. phosphorus
b. fluoride
• excessive intake may cause “dental fluorosis (mottling of teeth)”
c. calcium
d. magnesium
B
32
32. Most common environmental mineral toxic pollutant is: a. lead
b. nickel
c. cadmium d. vanadium
A
33
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33. The absorption of calcium is stimulated by which of the following vitamins?

a. beta-carotene
b. phylloquinone
c. calciferol
d. alpha-tocopherol
```
C
34
34. Which of the following minerals is essential in cytochrome oxidase synthesis? a. magnesium
b. copper c. iodine
• thyroid hormone synthesis d. molybdenum
• xanthine oxidase
B
35
35. Iron is stored in the liver almost entirely in the form of:
a. ferrous iron
b. hemosiderin
c. ferritin
d. transferrin
C
36
36. The type of anemia due to iron deficiency is which one of the following? a. aplastic
b. microcytic
• Iron deficiency Anemia- hyphochromia, microcytosis, poikilocytosis,
presence of target cells
c. macrocytic d. pernicious
• Vitamin B12 Anemia
B
37
37. The iron transport protein found in the plasma is: a. transferrin
b. ferritin
c. hemosiderin d. ceruloplasmin
A
38
38. Which of the following diseases is due to an abnormality in copper metabolism?
a. Minamata disease
• Mercury b. Itai-itai disease
• Cadmium c. Wilson’s disease
• excessive liver deposition of Copper d. Tetany
• Magnesium
C
39
39. The "turning of the points" stitching pattern in an ECG tracing is most likely due to which of the following?

a. Hyponatremia
b. Hypomagnesemia c. Hypophosphatemia d. Hypocalcemia
B
40
40. This is an endemic cardiomyopathy found in children and young women residing in regions of China where dietary intake of selenium is low:
a. Kashin-Beck disease
• deforming osteoarthritis associated with low plasma levels of Se in China,
Siberia, N. Korea b. Selenosis
• hair and nail brittleness and loss, etc. c. Menke’s disease
• genetic defect in intestinal absorption of Copper d. Keshan disease
D
41
41. The enzyme that cleaves ingested β-carotene to retinal in the intestinal lumen:
a. β – carotene dioxygenase
b. retinaldehyde reductase
c. retinal isomerase
d. alcohol dehydrogenase
A
42
42. True statement/s regarding vitamin A and vision:
a. 11-cis retinal is converted to all-trans retinal when rhodopsin absorbs light
b. The key to initiation of the visual cycle is the availability of 11-cis-retinaldehyde
c. The cyclic events in the visual process is known as rhodopsin cycle or Wald’s
vision cycle
d. All of these
D
43
43. All of
a. β – carotene
the following vitamins have antioxidant property, EXCEPT:
b. Ascorbic acid
c. Tocopherol
d. Cholecalciferol
D
44
44. The richest dietary sources of carotenoids are:
a. Meat
b. Green leafy vegetables
c. Cereals
d. Dairy products
B
45
45. Transport of retinol from the liver to extrahepatic tissues is facilitated by which of the following:
a. Retinol binding protein (RBP)
b. Cellular retinol binding protein (CRBP)
c. Albumin

d. Globulin
A
46
46. True statements regarding retinoic acid, EXCEPT:
a. It is involved in cellular expression as a regulator of gene expression
b. Retinoic acid is converted to all-trans retinal in the rhodopsin cycle/Wald’s visual
cycle
c. It is a steroid-like hormone with its receptors belonging to the nuclear receptor superfamily
d. Plasma transport of retinoic acid is accomplished by binding to albumin
B
47
47. Deficiency in vitamin D in children: a. Osteomalacia
• VItamin D deficiency in adults b. Osteoporosis
• Calcium defiency c. Rickets
d. Hemorrhagic disease of the new born
C
48
48. True statement/s regarding absorption and transport of vitamin D:
a. Exogenous Vitamin D is absorbed in the duodenum
b. It appears in the circulation as a constituent of chylomicrons
c. It is transported to the liver as chylomicron remnants
d. All of these
D
49
49. The active (most potent) form of vitamin D:
a. 1, 25 – dihydroxycholecalciferol
b. 25 – hydroxycholecalciferol
c. Cholecalciferol
d. 7-dehydrocholesterol
A
50
50. Role/s of vitamin D in calcium homeostasis:
a. Increased intestinal absorption of calcium and phosphate
b. Increased reabsorption of calcium and phosphate in the distal convoluted tubules
c. Mobilization of calcium and phosphate from bones
d. All of these
D
51
51. The most potent of the tocopherols: a. α-tocopherol
| b. tocotrienol c. β-tocopherol d. δ-tocopherol
A
52
52. The major site of vitamin E storage is:
a. Liver
b. Adipose tissue
c. Muscle

d. Bone
B
53
53. A synthetic vitamin K which can be absorbed even in the absence of bile salts: a. Phylloquinone
• form of vitamin K existing in plants (vitamin k1) b. Menaquinone
• form of vitamin k existing in intestinal bacterial flora (vitamin k2) c. Menadione
• synthetic; passing directly into the hepatic portal vein d. None of these
C
54
54. True statement/s regarding Vitamin K and blood clotting:
a. It is involved in the maintenance of normal levels of factors II, VII, IX and X
b. The reduced form of vitamin K is necessary for the activity of gamma-glutamyl
carboxylase
c. Vitamin K is needed for the normal activity of protein C, protein S and protein Z
d. All of these
D
55
55. Antihemorrhagic vitamin:
a. Vitamin A
b. Vitamin D
c. Vitamin E
d. Vitamin K
D
