Vitamins MCQs with Answers
Which vitamin functions like a hormone in the body?
- A. Vitamin D
- B. Vitamin B
- C. Vitamin C
- D. Vitamin E
Flavoproteins depend primarily on which vitamin?
- A. Vitamin B6
- B. Vitamin B2
- C. Vitamin B1
- D. Vitamin A
Which vitamin is produced by our gut bacteria?
- A. Vitamin B
- B. Vitamin A
- C. Vitamin D
- D. Vitamin K
Malonic aciduria appears with a deficiency of which vitamin?
- A. Pyridoxine
- B. Vitamin B12
- C. Folic acid
- D. Riboflavin
Which vitamin is absolutely essential for cell division (mitosis)?
- A. Folic acid
- B. Pantothenic acid
- C. Ascorbic acid
- D. Aspartic acid
Beri-beri results from a shortage of which vitamin?
- A. Thiamine
- B. Pyridoxine
- C. Ascorbic acid
- D. Riboflavin
A patient with kidney failure and bone pain likely lacks which vitamin?
- A. Vitamin A
- B. Vitamin B
- C. Vitamin C
- D. Vitamin D
Cereals are typically low in which nutrient?
- A. Vitamin C
- B. B-complex
- C. Iron
- D. Calcium
Vitamin C helps with:
- A. Procollagen maturation
- B. Osteoid matrix formation
- C. Osteoid calcification
- D. Both A and B
Vitamin B12 is also known as:
- A. Extrinsic factor
- B. Intrinsic factor
- C. Cyanocobalamin
- D. A fat-soluble vitamin
Which disorder is specific to vitamin B1 deficiency?
- A. Pellagra
- B. Angular cheilitis
- C. Megaloblastic anemia
- D. Peripheral polyneuritis
Which are the fat-soluble vitamins?
- A. A, B, D, K
- B. A, D, E, K
- C. A, B, E, K
- D. A, C, E, K
All are signs of vitamin A deficiency except:
- A. Night blindness
- B. Corneal dryness
- C. Bitot’s spots
- D. Myopia
The kidney’s active form of vitamin D is:
- A. 1-dihydroxy cholecalciferol
- B. 25-hydroxy cholecalciferol
- C. 1,25-dihydroxy cholecalciferol
- D. 7-dihydroxy calciferol
Which vitamin enhances iron absorption?
- A. Folic acid
- B. Ascorbic acid
- C. Biotin
- D. PABA
Vitamin K is antagonized by:
- A. Corticosteroids
- B. Thrombin
- C. Warfarin (coumarin)
- D. Liver clotting factors
Vitamin K’s main role is to:
- A. Form prothrombin
- B. Inhibit antithrombin
- C. Prevent capillary fragility
- D. Stimulate marrow
Night blindness (rhodopsin deficiency) is linked to:
- A. Vitamin D deficiency
- B. Rickets
- C. Vitamin A deficiency
- D. Scurvy
Pellagra arises from a lack of:
- A. Beri-beri
- B. Niacin
- C. Night blindness
- D. Pernicious anemia
Scurvy results from vitamin deficiency of:
- A. Vitamin A
- B. Vitamin C
- C. Vitamin B
- D. Vitamin D
Recommended daily intake of vitamin A is about:
- A. 1000 IU
- B. 2000 IU
- C. 3000 IU
- D. 4000 IU
Which forms of vitamin A are biologically active?
- A. Retinol
- B. Retinal
- C. Retinoic acid
- D. All of the above
Dermatitis, diarrhea and dementia (the 3 D’s) indicate deficiency of:
- A. Thiamin
- B. Riboflavin
- C. Niacin
- D. Pyridoxine
Vitamin K absorption depends on proper uptake of:
- A. Fat
- B. Amino acids
- C. Calcium
- D. Glucose
Which mineral is central to vitamin B12?
- A. Selenium
- B. Cobalt
- C. Iron
- D. Calcium
Vitamin K deficiency is shown by:
- A. Low platelets
- B. Increased prothrombin time
- C. Decreased prothrombin time
- D. None
Thiamine deficiency inhibits which reaction?
- A. Pyruvate → acetyl-CoA
- B. Citrate → α-ketoglutarate
- C. Succinyl-CoA → fumarate
- D. None
Vitamin K–dependent clotting factors include:
- A. II
- B. VII
- C. IX
- D. X
- E. All of the above
Which pairing of vitamin and its coenzyme form is incorrect?
- A. Biotin – carboxylated biotin
- B. Vitamin B – ATP
- C. Niacin – NAD+/NADP+
- D. Vitamin B2 – FMN/FAD
Vitamin B12 is absorbed in the:
- A. Stomach
- B. Terminal ileum
- C. Jejunum
- D. Proximal ileum
All of these are signs of vitamin C deficiency except:
- A. Swollen gums
- B. Abnormal collagen
- C. Anemia
- D. Diarrhea
Vitamin B12 is a cofactor for which enzyme?
- A. Isocitrate dehydrogenase
- B. Homocysteine methyltransferase
- C. Glycogen synthase
- D. G-6-P dehydrogenase
Vitamin A deficiency mainly affects:
- A. Solubility
- B. Vision
- C. Calcium levels
- D. Clotting factors
The richest source of vitamin E is:
- A. Cod liver oil
- B. Fish liver oil
- C. Wheat germ oil
- D. Liver
One molecule of β-carotene yields how many vitamin A units?
- A. 1
- B. 2
- C. 3
- D. 4
Thiamine deficiency lowers energy production because it’s a coenzyme for:
- A. Transamination
- B. Oxidative reduction
- C. Transketolase
- D. Pyruvate dehydrogenase
The earliest sign of vitamin A shortage is:
- A. Night blindness
- B. Bitot’s spots
- C. Dry mouth
- D. Conjunctival dryness
Which mineral spares vitamin E in the body?
- A. Chromium
- B. Iron
- C. Iodine
- D. Selenium
Which vitamin is a cofactor in glycine metabolism?
- A. Vitamin E
- B. Folic acid
- C. Thiamine
- D. B12
Vitamin C is found in highest concentration in:
- A. Eye
- B. Kidneys
- C. Testes
- D. Adrenal cortex
The tryptophan load test checks for deficiency of:
- A. Folic acid
- B. Niacin
- C. Pyridoxine
- D. B12
Which B12 form predominates in body stores?
- A. Methylcobalamin
- B. Hydroxocobalamin
- C. Cyanocobalamin
- D. None
Vitamin K’s action on clotting factors is via:
- A. Post-transcription
- B. Post-translation
- C. Golgi
- D. ER
Tocopherol is another name for:
- A. Vitamin A
- B. Vitamin E
- C. Vitamin K
- D. Vitamin D
Ascorbic acid acts as a:
- A. Reducing agent
- B. Iron absorption inhibitor
- C. Harmless in high doses
- D. Lysyl oxidase cofactor
Which factors delay wound healing?
- A. B12 deficiency
- B. Vitamin C deficiency
- C. Infection
- D. B & C
Xerophthalmia develops in deficiency of:
- A. Vitamin A
- B. Vitamin D
- C. Vitamin C
- D. Vitamin K
Recommended daily vitamin C intake is:
- A. 30–40 mg
- B. 50–60 mg
- C. 60–100 mg
- D. 100–150 mg
Which vitamin is central to one-carbon transfers?
- A. Niacin
- B. Thiamine
- C. Ascorbic acid
- D. Folic acid
Pernicious anemia is due to deficiency of:
- A. B1
- B. B12
- C. C
- D. D
The poorest source of vitamin C is:
- A. Milk
- B. Cabbage
- C. Guava
- D. Radish
Coenzyme A contains which vitamin?
- A. Biotin
- B. Pyridoxine
- C. Pantothenic acid
- D. Niacin
Niacin is synthesized from which amino acid?
- A. Tyrosine
- B. Tryptophan
- C. Threonine
- D. Histidine
Collagen formation is most affected by哪 vitamines deficiency?
- A. Vitamin A
- B. Vitamin C
- C. Vitamin B2
- D. Vitamin D
Niacin and riboflavin primarily assist in:
- A. Redox reactions
- B. Transamination
- C. Methyl transfers
- D. Amine transfers
Rich dietary sources of vitamin C include:
- A. Apples
- B. Fresh greens
- C. Citrus fruits
- D. Both B and C
Avidin in raw egg white can cause deficiency of:
- A. Biotin
- B. Niacin
- C. Thiamine
- D. Vitamin K
FIGLU excretion test diagnoses deficiency of:
- A. Vitamin K
- B. Vitamin B6
- C. Folic acid
- D. Niacin
All of these are signs of vitamin C deficiency except:
- A. Defective collagen synthesis
- B. Swollen gums
- C. Pigeon chest
- D. Subcutaneous hemorrhage
Peripheral neuropathy is seen in deficiency of:
- A. Pyridoxine
- B. Vitamin E
- C. Vitamin A
- D. Pantothenic acid
Eating raw egg white can lead to deficiency of:
- A. Riboflavin
- B. Biotin
- C. Thiamine
- D. Pyridoxine
Thiamine deficiency is confirmed by measuring:
- A. Blood thiamine levels
- B. Alkaline phosphatase
- C. RBC transketolase activity
- D. Plasma pyruvate/lactate
Both vitamins K and C play a role in:
- A. Clotting factor synthesis
- B. Post-translational modifications
- C. Antioxidant defense
- D. Microsomal hydroxylation
Biotin is essential for the function of:
- A. Pyruvate carboxylase
- B. Lactate dehydrogenase
- C. Succinate thiokinase
- D. Phosphohexose isomerase
Pellagra (aniacinosis) results in:
- A. Angular cheilitis
- B. Beri-beri
- C. Pellagra
- D. Night blindness
Who first demonstrated vitamin C’s role in preventing scurvy?
- A. Fracastorius
- B. James Lind
- C. John Snow
- D. Edward Jenner