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Biochemistry MCQs of VITAMINS, MINERALS & NUTRITION for 1st year MBBS Students

These MCQs are based on UHS BCQs and MCQs pattern but all 1st year MBBS students can get benefit from this rich content.

Note : Answers are in Bold form

1.  Which of the following co-factor is required for the synthesis of gamma amino butyric acid (GABA), serotonin , epinephrine, dopamine and histamine from their respective amino acid precursors:

a)  Tetrahydrobiopterin

b)  Tetrahydrofolate

c)  Pyridoxal phosphate

d)  Thiamine pyrophosphate

e)  Vitamin B12

2.  The effect of of a light impulse in the retina is:

a)  Isomereization of trans- retinal to cis- retinol.

b)  Reduction of 11 cis- retinol to cis- retinol

c)  Isomerization ofcis- retinol to tran-retinol

d)  Reduction of trans- retinal to trans-retinol.

e)  Isomerization of 11 cis-retinal to trans- retinal.

3.  Two vitamins whose derivatives are involved in the transformation of serine to glycine are:

a)  B12 and nicotinamisde.

b)  Folic acid and vitamin B6.

c)  B6 AND B12.

d)  Folic acid and B12.

e)  Pyridoxal phosphate and B12.

4.   A women with a lactase deficiency who eats no dietary products:

a)  Cannot produce mucopolysaccharodes that contains galactose.

b)  Cannot produce lactose during lactation,

c)  Is likely tom suffer from a calcium deficiency .

d)  Is likely to have high cellular levels of galactose 1 Phosphate.

e)  Cannot produce mucopolysaccharides that contain mannose.

5.   Which one of the following nutrients is a precursor for a co-factor that carries one carbon groups of different oxidation states:

a)  Methioinine.

b)  Thiamine.

c)  Folic acid.

d)  Biotin.

e)  Pyridoxine.

6.  Which one of the following would be seen in a patient with a severe thiamine deficiency:

a)  Decreased serum levels of pyruvate and lactate.

b)  Increased clotting time of blood.

c)  Low red cell tranamknase activity..

d)  Increased urinary excretion of xanthurenic acid following a tryptophan load.

e)  Decreased transketolase activity in RBCs.

7.  Consumption of raw eggs, which contain the protein avidin could lead to deficiency resulting in:

a)  An Inhibition of dacrboxylation reactions.

b)  An inability to form acetylcholine.

c)  A decrease in Co-A formation.

d)  An increase in trans aminations.

e)  An inhibition of carboxylation reactions.

8.  The active form of the cofactor required for oxidative decarboxylation reactions is:

a)  Thiamine mono phiosphate.

b)  Thiamine.

c)  Thiamine pyrophosphate.

d)  Thiamine triphosphate.

e)  Hydoxyethyl thiamine proiphosphate.

9.  Vitamin K plays an essential role in:

a)  Dissolving blood clots.

b)  Post-translational modification of some proteins.

c)  Maintenance of the retina integrity.

d)  Preventing bile stasis.

e)  Biosynthesis of factor XI.

10.              The nutritional role of the carotenoids lies in their conversion in vivo to:

a)  Ascorbic acid.

b)  Cobalamine.

c)  Folic acid.

d)  Prostaglandins.

e)  Vitamin A.

11.              Which of the following vitamins would most likely become deficient in  a person who develops a completely carnivorous lifestyle:

a)  Thiamine.

b)  Niacin

c)  Cobalamine.

d)  Panthothenic acid.

e)  Vitamin C.

12.              Children with autism and other disorders with mental disability are often put on megavitamin supplements despite no scientific evidence of benefit. Although most vitamins are harmless in excess, merely being excreted in urine, vitamin A can be toxic. Which of the following statements regarding vitamin A  is true:

a)  It is not an essential vitamin.

b)  It is related to tocopherol.

c)  It is component of rhodopsin.

d)  It is derived from ethanol.

e)  It is also known as opsin.

13.              Which of the following foods should be emphasized for individuals with peripheral neuritis, insomnia, mouth and skin irritation and diarrhea?

a)  Human and cow (not gout) milk, uncooked fruits and vegetables.

b)  Milk, eggs, meat and fruits.

c)  Vegetables, cereals and fruits.

d)  Liver, poultry and eggs.

e)  Egg yolks, fish oils and leafy vegetables.

14.              Which one of the following is definitely associated with a human disease when deficient?

a)  Arsenic.

b)  Lead.

c)  Zinc.

d)  Antimony.

e)  Vanadium.

15.  A homeless person is brought into the emergency room with psychiatric imagery and alcohol on his breath. Which of the following compounds is most important to administer?

a)  Glucose.

b)  Niacin.

c)  Nicotinic acid.

d)  Thiamine.

e)  Riboflavin.

16. An important etiologic factor in kwashiorkor is:

a)  Excess dietary ethionine.

b)  Steatorrhea.

c)  Anemia.

d)  Dietary protein deficiency.

e)  Dietary mineral deficiency.

17. A term infant is born at home and does well with breast-feeding. Two days later, the mother calls frantically because the baby is bleeding from the umbilical cord and nostrils. The most likely cause is:

a)   Deficiency of vitamin C due to a citrus-poor diet during pregnancy

b)   Hypervitaminosis A due to ingestion of beef liver during pregnancy

c)   Deficiency of vitamin K because infant intestines are sterile.

d)   Deficiency of vitamin K because of disseminated intravascular coagulation (disseminated clotting due to infantile sepsis)

e)   Deficiency of vitamin E due to maternal malabsorption during pregnancy.

18.  Humans most easily tolerate a lack of which of the following nutrients?

a)   Protein

b)   Iodine

c)   Carbohydrate

d)   Lipid

e)   Calcium

19. Given the information that a 70-kg man is consuming a daily average of 275 g of carbohydrate, 75 g of protein, and 65 g of lipid, one can draw which of the following conclusions?

a)  Total energy intake per day is approximately 3000kcal.

b)  About twenty percent of the calories are derived from lipids.

c)  The diet does not contain a sufficient amount of dietary fiber.

d)  The proportions of carbohydrate, protein, and lipidin the diet conform to the recommendations of academic groups and government agencies.

e)  The individual is in nitrogen balance.

20.              Which one of the following statements concerning dietary lipid is correct?

a)  Corn oil and soybean oil are examples of fats rich in saturated fatty acids.

b)  Triacylglycerols obtained from plants generally contain less unsaturated fatty acids than those from animals.

c)  Olive oil is rich in saturated fats.

d)  Fatty acids containing double bonds in the trans-configuration, unlike the naturally occurring cis isomers, raise plasma cholesterol levels.

e)  Coconut and palm oils are rich in polyunsaturated fats.

21.     Pyridoxine deficiency can occur in tubercular patients taking:

a)  Isoniazid

b)  Paraminosalycilate

c)  Streptomycin

d)  Thiacetazone

e)  Diclofenac sodium

22.  Consumption of raw egg white can produce neurological abnormalities by blocking the absorption of:

a)  Pyridoxine

b)  Biotin

c)  Thiamin

d)  Lipoic acid

e)  Ascorbic acid

23  Human being cannot synthesize ascorbic acid because they lack :

a)  Ascorbate dehydrogenase

b)  Xylulose reductase

c)  L-gulonate dehydrogenase

d)  L-gulonolactone oxidase

e)  Aspartate dehydrogenase

24.      When light falls on rod cells:

a)  All-cis retinal is converted into all -trans retinal

b)  11 cis-retinal is converted into 11 trans-retinal

c)  11 trans-retinal is converted into all trans-retinal

d)  11 cis retinal is converted into all-trans retinal

e)  11 cis –retinal is converted into 11cis-retinol

25.              Polyunsaturated fatty acids:

a)  Lowers LDL and HDL is also lowered

b)  Increase LDL but decrease HDL also

c)  Decreases LDL but HDL is also decreased

d)  Decrease IDL but HDL is also decreased

e)  Increase IDL but HDL is also decreased

26.              Leptin is the hormone which:

a)  Increases the metabolic role and decreases appetite

b)  Increases the number of fat cells and decreases LDL

c)  Increases the human obesity

d)  Decreases the number of cells and increases obesity

e)  Decreases the metabolic role and increases appetite

27.  Intestinal bacteria can synthesize:

a)  Phyloquinone

b)  Menaquinone

c)  Menadione

d)  Tocopherol

e)  Retinol

28.              A high plasma calcium level decreases intestinal absorption of calcium by:

a)  Stimulating the secretion of paratharmone

b)  Inhibiting the secretion of  paratharmone

c)  Decreasing the synthesis of cholecalciferol

d)  Inhibiting the secretion of thyrocalcitonin

e)  Increasing the synthesis of cholecalciferol

29.              The correct statement about serum inorganic phosphorus concentration is :

a)  It is higher in men than in women

b)  It is higher in women than in men

c)  It is higher in adults than in children

d)  It is higher in children than in adults

e)  It is higher both in female children and adults


30.              Consumption of iodized  salt is recommended in:

a)  Patients with hyperthyroidism

b)  Patient with hypothyroidism

c)  Pregnant women

d)  Goiter belt areas

e)  Lactating women

31.              Copper deficiency can cause:

a)  Polycythemia

b)  Leukocytopenia

c)  Thrombocytopenia

d)  Microcytic anaemia

e)  Iron deficiency anaemia

32.              Zinc is a cofactor for:

a)  Acid-phosphatase

b)  Alkaline phosphatase

c)  Amylase

d)  Lipase

e)  Pepsin

33.              In which of the following physical activity, energy consumed is maximum:

a)  Typing at high speed

b Swimming

c)  Walking uphill

d)  Cycling

e)  Tailoring

34.              A young accountant consumes three cups of strong black coffee during his office hours. Strong coffee has following effects  on his  metabolism:

a)  Decrease effect on glucagon

b)  Provide vitamin nicotinic acid

c)  Interfere with synthesis of prostaglandins

d)  Enhance effect of insulin

e)  Enhance the effect of epinephrine