[SGD Recalls] - Vitamin B12 Deficiency Flashcards
Release Vit from protein binding food A. Gastric B. Pepsin C. Gastric and pepsin D. NOTA
C. Gastrin and pepsin
Present in saliva that binds B12 A. Transcobalamin I B. Transcobalamin II C. Cobalophilin D. IF
C. Cobalophilin
After reaching the stomach it binds to A.Transcobalamin I B.Transcobalamin II C. Cobalophilin D. IF
D. IF
Bind into this that transports it to the liver
A.Transcobalamin I
B.Transcobalamin II
C. Cobalophilin
D. IF
A.Transcobalamin I
Secreted by parietal cells in gastric mucosa
A. Transcobalamin I
B. Transcobalamin II
C. Cobalophilin
D. IF
D. IF
Site of absorption of B12
A. Duodenum
B. Stomach
C. Jejunum
D. Ileum
D. Ileum
Most potent test to use in determining B12
A. MMA test
B. PBS
C. Folate level
A. MMA test
An enzyme in which the B12 is the cofactor of it for the conversion of MMA to Succinyl Coa
A. Methionine Synthase
B. Succinyl Coa mutase
C. Methyl Malonic CoA mutase
C. Methyl Malonic CoA mutase
Plasma protein-binding
Ans: TRANSCOBALAMIN II
What is the common cause of pernicious anemia?
Ans: Failure of the absorption of Vit. B12
Which of the following are Vit. B12 dependent, EXCEPT?
a. Methyl malonyl coA
b. Leucine aminomutase
c. Methyl aminomutase
d. Methionine synthase
c. Methyl aminomutase
What secretes IF?
Ans: Parietal cells in gastric mucosa
Is a free Intrinsic Factor or free Vit. B12 absorbed in ileum?
TRUE
FALSE
FALSE
If there is pancreatic insufficiency what causes Vit. B12 deficiency?
Ans: Prevents hydrolysis of TCNI in duodenum
What reaction leads to Vit. B12?
Ans: Methyltetrahydrofolate to THF
What enzyme is responsible for the conversion of methionine from homocysteine?
Ans: Methylcobalamin
What is the cofactor for Methylmalonyl CoA to Succinyl CoA isomerization?
Ans: Adenosyl cobalamin
What is the specific test for Vit. B12 deficiency?
Ans: Methyl Malonic Acid Test (MMA)
What characteristic erythrocyte feature is seen among patients with Vitamin B12 deficiency?
a. Hypochromic, normocytic RBC
b. Hypochromic, microcytic RBC
c. Hyperchromic, normocytic RBC
d. Hypochromic, macrocytic RBC
d. Hypochromic, macrocytic RBC
In Vitamin B12 absorption, the vitamin is released from protein binding in food by:
a. pepsin
b. cobalophilin
c. gastric acid and cobalophilin
d. gastric acid and pepsin
d. gastric acid and pepsin
True of Vitamin B12 except:
a. derived from animal source
b. requires a glycoprotein for absorption
c. cofactor form is methylcobalamin
d. cofactor form is deoxycobalamin
b. requires a glycoprotein for absorption?
What is the specific transport protein of Vit. B12 to plasma?
a. Transcobalamin I
b. Transcobalamin II
c. Cobalophilin
d. Intrinsic Factor
b. Transcobalamin II
What test can be used to confirm malabsorption of Vit. B12?
a. Sickle Test
b. Ferritin Test
c. Spectrin Test
d. Schilling Test
d. Schilling Test
More specific test for diagnosis?
Ans. Methylmalonate test (MMA)
Glycoprotein secreted by salivary and gastric glands that carries free cobalamin
Ans. Haptocorrin (R protein)
Best method for cobalamin administration
Ans. Parenteral route
