MCQs INTRODUCTION TO BIOCHEMISTRY

1. A drug which prevents uric acid synthesis
by inhibiting the enzyme xanthine
oxidase is
(A) Aspirin (B) Allopurinol
(C) Colchicine (D) Probenecid
2. Which of the following is required for
crystallization and storage of the
hormone insulin?
(A) Mn++ (B) Mg++
(C) Ca++ (D) Zn++
3. Oxidation of which substance in the body
yields the most calories
(A) Glucose (B) Glycogen
(C) Protein (D) Lipids
4. Milk is deficient in which vitamins?
(A) Vitamin C (B) Vitamin A
(C) Vitamin B2 (D) Vitamin K
5. Milk is deficient of which mineral?
(A) Phosphorus (B) Sodium
(C) Iron (D) Potassium
6. Synthesis of prostaglandinsis is inhibited
by
(A) Aspirin (B) Arsenic
(C) Fluoride (D) Cyanide
7. HDL is synthesized and secreted from
(A) Pancreas (B) Liver
(C) Kidney (D) Muscle
8. Which are the cholesterol esters that enter
cells through the receptor-mediated
endocytosis of lipoproteins hydrolyzed?
(A) Endoplasmin reticulum
(B) Lysosomes
(C) Plasma membrane receptor
(D) Mitochondria
9. Which of the following phospholipids is
localized to a greater extent in the outer
leaflet of the membrane lipid bilayer?
(A) Choline phosphoglycerides
(B) Ethanolamine phosphoglycerides
(C) Inositol phosphoglycerides
(D) Serine phosphoglycerides
10. All the following processes occur rapidly
in the membrane lipid bilayer except
(A) Flexing of fatty acyl chains
(B) Lateral diffusion of phospholipids
(C) Transbilayer diffusion of phopholipids
(D) Rotation of phospholipids around their long
axes
11. Which of the following statement is
correct about membrane cholesterol?
(A) The hydroxyl group is located near the centre
of the lipid layer
(B) Most of the cholesterol is in the form of a
cholesterol ester
(C) The steroid nucleus form forms a rigid, planar
structure
(D) The hydrocarbon chain of cholesterol projects
into the extracellular fluid
12. Which one is the heaviest particulate
component of the cell?
(A) Nucleus (B) Mitochondria
(C) Cytoplasm (D) Golgi apparatus
13. Which one is the largest particulate of the
cytoplasm?
(A) Lysosomes
(B) Mitochondria
(C) Golgi apparatus
(D) Entoplasmic reticulum
14. The degradative Processess are categorized
under the heading of
(A) Anabolism (B) Catabolism
(C) Metabolism (D) None of the above
15. The exchange of material takes place
(A) Only by diffusion
(B) Only by active transport
(C) Only by pinocytosis
(D) All of these
16. The average pH of Urine is
(A) 7.0 (B) 6.0
(C) 8.0 (D) 0.0
17. The pH of blood is 7.4 when the ratio
between H2CO3 and NaHCO3 is
(A) 1 : 10 (B) 1 : 20
(C) 1 : 25 (C) 1 : 30
18. The phenomenon of osmosis is opposite
to that of
(A) Diffusion (B) Effusion
(C) Affusion (D) Coagulation
19. The surface tension in intestinal lumen
between fat droplets and aqueous
medium is decreased by
(A) Bile Salts (B) Bile acids
(C) Conc. H2SO4 (D) Acetic acid
20. Which of the following is located in the
mitochondria?
(A) Cytochrome oxidase
(B) Succinate dehydrogenase
(C) Dihydrolipoyl dehydrogenase
(C) All of these
21. The most active site of protein synthesis
is the
(A) Nucleus (B) Ribosome
(C) Mitochondrion (D) Cell sap
22. The fatty acids can be transported into
and out of mitochondria through
(A) Active transport
(B) Facilitated transfer
(C) Non-facilitated transfer
(D) None of these
23. Mitochondrial DNA is
(A) Circular double stranded
(B) Circular single stranded
(C) Linear double helix
(D) None of these
24. The absorption of intact protein from the
gut in the foetal and newborn animals
takes place by
(A) Pinocytosis (B) Passive diffusion
(C) Simple diffusion (D) Active transport
25. The cellular organelles called “suicide
bags” are
(A) Lysosomes (B) Ribosomes
(C) Nucleolus (D) Golgi’s bodies
26. From the biological viewpoint, solutions
can be grouped into
(A) Isotonic solution
(B) Hypotonic solutions
(C) Hypertonic solution
(D) All of these
27. Bulk transport across cell membrane is
accomplished by
(A) Phagocytosis (B) Pinocytosis
(C) Extrusion (D) All of these
28. The ability of the cell membrane to act as
a selective barrier depends upon
(A) The lipid composition of the membrane
(B) The pores which allows small molecules
(C) The special mediated transport systems
(D) All of these
29. Carrier protein can
(A) Transport only one substance
(B) Transport more than one substance
(C) Exchange one substance to another
(D) Perform all of these functions
30. A lipid bilayer is permeable to
(A) Urea (B) Fructose
(C) Glucose (D) Potassium
31. The Golgi complex
(A) Synthesizes proteins
(B) Produces ATP
(C) Provides a pathway for transporting chemicals
(D) Forms glycoproteins
32. The following points about microfilaments
are true except
(A) They form cytoskeleton with microtubules
(B) They provide support and shape
(C) They form intracellular conducting channels
(D) They are involved in muscle cell contraction
33. The fo l low ing substances are ce l l
inclusions except
(A) Melanin (B) Glycogen
(C) Lipids (D) Centrosome
34. Fatty acids can be transported into and
out of cell membrane by
(A) Active transport (B) Facilitated transport
(C) Diffusion (D) Osmosis
35. Enzymes catalyzing electron transport
are present mainly in the
(A) Ribosomes
(B) Endoplasmic reticulum
(C) Lysosomes
(D) Inner mitochondrial membrane
36. Mature erythrocytes do not contain
(A) Glycolytic enzymes(B) HMP shunt enzymes
(C) Pyridine nucleotide(D) ATP
37. In mammalian cells rRNA is produced
mainly in the
(A) Endoplasmic reticulum
(B) Ribosome
(C) Nucleolus
(D) Nucleus
38. Genetic information of nuclear DNA is
transmitted to the site of protein synthesis
by
(A) rRNA (B) mRNA
(C) tRNA (D) Polysomes
39. The power house of the cell is
(A) Nucleus (B) Cell membrane
(C) Mitochondria (D) Lysosomes
40. The d igest ive enzymes of ce l lu lar
compounds are confined to
(A) Lysosomes (B) Ribosomes
(C) Peroxisomes (D) Polysomes

ANSWERS
1. B 2. D 3. D 4. A 5. C 6. A
7. B 8. B 9. A 10. C 11. C 12. A
13. B 14. B 15. D 16. B 17. B 18. A
19. A 20. D 21. B 22. B 23. A 24. A
25. A 26. D 27. D 28. D 29. D 30. A
31. D 32. C 33. D 34. B 35. D 36. C
37. C 38. D 39. C 40. A