1. Millon's test is performed to check the presence of
a. Soluble
proteins with tyrosine
b. Soluble
carbohydrates
c. Lipids
d. Soluble
proteins without tyrosine
Correct answer: a, Millon's test is performed to detect the presence
of soluble proteins. Millon's test detects tyrosine. Since tyrosine is an amino
acid occurring in nearly all proteins, Millon's test is used for detecting
proteins.
2. Which of the following polysaccharides is composed of repeated
fructose units?
a. Chitin
b. Inulin
c. Pectin
d. Hemicellulose
Correct Answer: b, Inulin is a fructosan. It is composed of fructose
units in furanose form. In inulin, the fructose residues are joined together in
a straight chain by beta-2,1 glycosidic linkages.
3. under optimum condition, the enzyme having the highest turnover
number, among the following, is:
a. Beta amylase
b.
Acetylcholinesterase
c. Carbonic
anhydrase
d. Lysozyme
Correct answer: c, Carbonic anhydrase has the highest turnover number.
It catalyzes the rapid interconversion of carbon dioxide and water to
bicarbonate and protons. Its turnover number is 6,00,000
4. Which amino acid accounts for about 20% of the amino acid content
of the protein of human hair?
a. Proline
b. Methionine
c. Tyrosine
d. Cysteine
Correct Answer: d, Cysteine accounts for about 20% of the amino acid
content of the protein of human hair. The protein of human hair is Keratin
5. All the following mucopolysaccharides are synthesized in the Golgi
apparatus, except
a. Hyaluronidase
b. Heparin
c. Chondroitin
sulfate
d. Keratan
sulfate
Correct answer: a, Hyaluronidase is not synthesized by the Golgi, but
rather by integral membrane synthases which immediately secrete the dynamically
elongated disaccharide chain.
6. Hyaluronic acid is characterized by the presence of
a. beta 1,3 linkage
b. beta 1,4 linkage
c. alpha 1,4 linkage
d. alpha 1,6 linkage
a. c and d
b. a and b
c. a and d
d. b and c
Correct Answer: b, Hyaluronic acid is characterized by the presence of
beta 1,3 and beta 1,4 linkages
7. With which of the following enzymes are no coenzyme or metal ions
associated?
a.
Carboxypeptidase A
b. Ribonuclease P
c. Lysozyme
d. Carbonic
anhydrase
Correct answer: c, Lysozyme consists of a single polypeptide chain of
129 amino acid residues having no coenzyme or metal ion cofactors.
8. The domain(s) of myosin that uses ATP hydrolysis to generate
force is/are
a. Head domain
b. Neck domain
c. Tail domain
d. Both head and
neck domain
Correct answer: a, The head domain binds the
filamentous actin and uses ATP hydrolysis to generate force.
9. Which of the following lipids is concentrated in the highest
percentage in nerve tissues?
a. Phospholipids
b. Cholesterol
c. Cerebrosides
d. Sulfur-containing lipids
Correct answer: The percentage of phospholipids in nerve tissue is 28,
which is the highest percentage of lipids in the nerve tissue.
10. Sulfanilamides block the folic acid synthesis in microorganisms by
a. Irreversible
non-competitive inhibition
b. Reversible
non-competitive inhibition
c. Competitive
inhibition
d. Un-competitive
inhibition
Correct answer: Sulfanilamide is a structural analog of
p-aminobenzoate (substrate for folic acid synthesis) and binds free enzymes at
the site where the substrate binds, thus it blocks folic acid synthesis by
competitive inhibition.
11. Homocysteine is an amino acid produced from adenosine. This amino
acid is associated with
a. Osteoporosis
b. Gout
c.
Atherosclerosis
d. Osteomyelitis
Correct answer: c, Homocysteine is an amino acid produced by chemical
alteration of adenosine. Increased levels of homocysteine are associated with
atherosclerosis.
a. Low dietary
zinc intake
b. Reduced
excretion via kidneys
c. Fasting
d. Both fasting
and reduced excretion via kidneys
Correct answer: a, Low dietary zinc intakes cause lower uric acid
levels.
13. Besides galactose, glucose is also epimeric with
a. Fructose
b. Maltose
c. Altrose
d. Mannose
Correct Answer: d, Glucose is epimeric with mannose. Both of them
differ in C2 configuration
14. A blue-colored Ruhemann's complex is formed when amino-acids
undergo
a. Reaction with
Sanger’s reagent
b. Ninhydrin
reaction
c. Acylation
reaction
d. Van Slyke
reaction
Correct Answer: b, In ninhydrin reaction, the ninhydrin reagent causes
oxidative decarboxylation of alpha-amino acids and produces CO2, NH3, and an aldehyde with one less carbon
atom than the parent amino acid. The reduced ninhydrin then reacts with the
liberated NH3 and a
mole of ninhydrin, forming blue-colored Ruhemann's complex.
15. Which of the following statements regarding carbohydrate
metabolism is erroneous?
a. Both
hexokinase and glucokinase are stimulated by insulin
b. Glycogen gives a red color with iodine
c. Glycogen and
cellulose, both are glucosans
d. Chitin yields
N-acetylglucosamine on hydrolysis
Correct answer: a, Hexokinase is not induced by insulin while
glucokinase is induced by insulin.
16. Although uracil replaces thymine in RNA, in which of the RNAs can
a small amount of thymine be found?
a. rRNA
b. tRNA
c. Prokaryotic
mRNA
d. Eukaryotic
mRNA
Correct Answer: b, A minor amount of thymine is found in the T-arm of some
tRNA. The T-arm or T-loop is a specialized region on the tRNA molecule
which acts as a special recognition site for the ribosome to form a
tRNA-ribosome complex during protein biosynthesis. Presence of thymine in
T-arm has to do with binding to ribosome and methylation of the site.
17. Which of the following fatty acids are end products of
carbohydrate fermentation by rumen microorganisms?
a. Acetic acid
b. Caproic acid
c. Butyric acid
d. Caprylic acid
a. a and b
b. a,c, and d
c. a,b, and c
d. a,b,c and d
Correct answer: c, Acetic acid, caproic acid and butyric acid all are
end products of carbohydrate fermentation by rumen microorganisms.
18. Cysteic acid is a naturally occurring amino acid that is found in
a. Cat’s urine
b. Human brain
tissue
c. Rat brain
tissue
d. Sheep’s fleece
Correct Answer: d, Cysteic acid occurs normally in the outer part of
the sheep's fleece, where the wool is exposed to light and weather.
19. Which one of the following is an aldopentose?
a. D-arabinose
b.
Glyceraldehydes
c. Ribulose
d. D-erythrose
Correct answer: a, D-Arabinose is an aldopentose, a monosaccharide
containing five carbon atoms, and including an aldehyde (CHO) functional group.
20. Nucleoproteins like histones can be more easily obtained from
a. Yeast cells
b. Thymus gland
c. Mesophyll cells
d. Cheek cells
a. a and b
b. a and c
c. c and d
d.b and d
Correct answer: a, Nucleoproteins can be more easily isolated from
yeast cells and thymus gland because these cells have large nuclei
21. In which carbohydrates are S-type glycosidic bonds found?
a. Sucrose
b. Thioglycosides
c. Glycosylamines
d. Starch
Correct Answer: b, S-glycosidic bonds are found in thioglycosides,
where the sulfur atom is bonded in place of oxygen in the glycosidic bond.
22. Which of the following amino acids is a conditionally essential
amino acid?
a. Phenylalanine
b. Valine
c. Arginine
d. Serine
Correct answer: c, Arginine can normally be synthesized by an
organism, but under certain conditions, such biosynthesis is not enough to
prevent a deficiency syndrome; thus, it is a conditionally essential amino
acid.
a. Thymine
b. Cytosine
c. Adenine
d. Guanine
Correct Answer: d, Guanine on deamination yields xanthine, a purine
base found in most human body tissues and fluids, and in other organisms.
24. Which of the following naturally occurring amino acids act as a
part of pantetheine and coenzyme A?
a. Homoserine
b. Taurine
c. Beta-alanine
d. Alpha
amino-butyric acid
Correct answer: c, Beta-alanine is a component of pantothenic acid
(vitamin B5), which itself is a component of coenzyme A.
25. Which of the following statements is true about candelilla
wax?
a. It is obtained
from insects
b. It is hard
yellowish-brown wax
c. It is the only
water-soluble wax
d. It has low
hydrocarbon content
Correct answer: Candelilla wax is a yellowish-brown, hard wax.
26. Which of the following statements is false about D-galactose?
a. It is obtained
on hydrolysis of the lactone
b. It is
completely fermented by yeast
c. It is an
epimer of glucose
d. Galactose is
metabolized in the Leloir pathway
Correct Answer: b, Galactose is fermented by yeast but complete
fermentation is not achieved.
27. Which of the following amino acids has a breaking action on the
alpha-helix structure of a protein?
a. Alanine
b Proline
c. Methionine
d. Threonine
Correct Answer: b, Proline breaks the alpha-helix. The N2atom
of proline is part of a rigid ring and no rotation of N-C bond can occur.
28. Which of the biological functions can be attributed to amino acid
isoleucine?
a. Prevents the
breakdown of muscle tissue
b. Prevents the
use of muscle glucose
c. Recovery of
muscle tissue after physical stress
d. Formation of
creatine in the body
Correct answer: c, Isoleucine aids in the recovery of muscle tissue
after physical stress like a severe workout.
29. Cholesterol translocation from the outer to the inner membrane of
mitochondria is done by
a. Cephalin
b. Choline
c. Cardiolipin
d. Lipositol
Correct answer: c, Cardiolipin is a phospholipid found in the mitochondrial membrane which translocates cholesterol from the outer to the inner
membrane of mitochondria.
30. Which color is produced when achrodextrin is treated with an iodine
solution?
a. Red color
b. White color
c. Red color
d. No color
Correct Answer: d, Achrodextrin does not yield any color when
hydrolyzed with iodine solution.
31. What does monosaccharide ribose function as?
a. Storage
molecule
b. Enzyme
c. Co-factor
d. Blood clotter
Correct answer: c, Ribose functions as co-enzyme in several metabolic
pathways. It acts as a derivative of coenzyme A.
32. In which organisms are the amino acid pyrrolysine found?
a. Corncokles
b. Archea
c. Solomon’s
seals
d. Soybeans
Correct Answer: b, Pyrrolysine is an ɑ-amino acid that is used in the
biosynthesis of proteins in some methanogenic archaea and bacteria.
33. Which is the largest and most structurally complicated vitamin?
a. Vitamin D
b. Vitamin C
c. Vitamin B12
d. Vitamin B6
Correct answer: c, Vitamin B12 is the largest and
most structurally complicated vitamin. It can be produced industrially only
through bacterial fermentation synthesis.
34. As per the number of saccharide units, what is gentianose?
a. Monosaccharide
b. Disaccharide
c. Trisaccharide
d.
Tetrasaccharide
Correct answer: c, Gentianose is a trisaccharide. Gentianose is
composed of two units of glucose and one unit of fructose.
35. Glucose and galactose are
a. Enantiomers
b. Epimers
c. Geometrical
isomers
d. Optical
isomers
Correct Answer: b, Glucose, and galactose form an epimeric pair as they
differ with respect to carbon-4 only.
36. Which of the following is the sweetest sugar?
a. Saccharin
b. Monellin c. D-fructose
d. Maltose
Correct Answer: b, The sweetest sugar is monellin. Its relative
sweetness is 2000.
37. In which biological entity is the amino acid orcylalanine found?
a. Salmon sperm
b. Corn
c. Corncockle
d. Solomon’s seal
Correct answer: In seeds of corncockle, the amino acid orcylalanine
is found. It is considered to be substituted phenylalanine.
38. What type of structure does myoglobin protein possess?
a. Primary
b. Secondary
c. Tertiary
d. Quaternary
Correct answer: Myoglobin has a tertiary structure.
39. ___________ is the unsaturated alcohol found in tomatoes.
a. Phytol
b. Lycophyll
c. Lauryl alcohol
d. Cetyl alcohol
Correct Answer: b, Lycophyll is found in tomatoes as a purple pigment.
It is unsaturated alcohol.
40. Butter is a common source of
a. elicosanoic
acid
b. Dodecanoic
acid
c. Butanoic acid
d. Hexanoic acid
Correct answer: c, Butter is a common source of butanoic acid. It has
an unpleasant smell and acrid taste, with a sweetish aftertaste similar to
ether.
41. Why does denaturation of an enzyme make it non-functional?
a. Rearrangement
of the amino-acid sequence takes place
b. The 3D shape
of the enzyme is disrupted
c. Peptide bonds
break and amino acids is formed
d. New peptide
bonds are formed
Correct answer: The enzyme loses its function on denaturation
because the 3D shape of the enzyme is disrupted. Due to disruption of shape,
the active site is no more available.
42. Which amino acid is completely destroyed upon acid hydrolysis?
a. Phenylalanine
b. Tryptophan
c. Asparagine
d. Glutamic acid
Correct Answer: b, Tryptophan is the only amino acid of proteins
which is completely destroyed upon acid hydrolysis.
43. Which of the following oils has the least iodine number?
a. Palm oil
b. Coconut oil
c. Tung oil
d. Peanut oil
Correct Answer: b, Coconut oil has the least iodine number. It is
7-12. Iodine numbers determine the amount of unsaturation in fatty acids. Coconut
oil is very saturated and thus, has less iodine number.
44. Which of the following is not present in a nucleoside?
a. Beta
glycosidic linkage
b. Nitrogenous
base
c. Phosphoric
acid
d. Pentose sugar
Correct answer: c, Phosphoric acid is not present in a nucleoside.
45. Siderophillin is a protein in which a metal is strongly bound by
proteins. Which metal is strongly bound in siderophillin?
a. Copper (Cu)
b. Iron (Fe)
c. Zinc (Zn)
d. Calcium (Ca)
Correct answer: b. Siderophilin has Fe strongly bound by proteins. It
is an important metalloprotein and constitutes about 30% of plasma protein. It
facilitates iron transport.
46. A polysaccharide on hydrolysis yields D-fructose. The
polysaccharide probably is
a. Inulin
b. Cellulose
c. Glycogen
d. Chitin
Correct answer: a, Inulin on hydrolysis yields D-fructose.
47. Casein of milk and vitellin of egg consists of proteins bound to
a. Metal group
b. Phosphate
group
c. Carbohydrate
d. Lipids
Correct Answer: b, Casein of milk and vitellin of the egg are
phospho-proteins, i.e. they are composed of protein and phosphate.
48. Select the erroneously paired amino acids.
a.
Lysine-Arginine
b.
Methionine-Cysteine
c. Serine-Valine
d.
Serine-threonine
Correct answer: c, Serine has a polar R group, whereas valine has a
non-polar R group.
49.
Structural formulae are correctly paired with its related function
or property in which of the following options?
a. B-Trehalose- A
component of insect hemolymph
b. A-Glutamic
acid- Component of wheat gluten
c. B-Cellobiose-
reducing sugar
d.
A-Cytosine-Component of DNA
Correct answer: a, B is trehalose. Trehalose, the non-reducing
disaccharide of glucose is the principal sugar circulating in the blood or
hemolymph of most insects. Resistance to acid hydrolysis and an absence of
direct intramolecular hydrogen bonding makes trehalose chemically unique when
compared with other common disaccharides, particularly sucrose, the
non-reducing disaccharide of plant origin.
50. Which of the following is an essential amino acid?
a. Leucine
b. Alanine
c. Glycine
d. Proline
Correct answer: Leucine is an essential amino acid. An essential
amino acid, or indispensable amino acid, is an amino acid that cannot be
synthesized by the organism, and thus must be supplied in its diet.
51. An oligosaccharide involves beta-1,4-glucoside linkage in binding
its constituent monosaccharides. The constituent monosaccharides of the
oligosaccharide are
a. α-D-glucose and
α-D-glucose
b. β-D-glucose and β-D-glucose
c. β-D-glucose and
α-D-glucose
d.
None of these
Correct Answer: b, The beta-1,4-glucoside
linkage is found in cellobiose. Its constituent monosaccharides are β-D-glucose
and D-glucose.
52. In a reaction of reagent X and glucose, gluconic acid is obtained.
The reagent X is:
a. Benedict’s
reagent
b. Fehling’s
solution
c. Tollens’
reagent
d. Barfoed’s
reagent
Correct Answer: Glucose gives gluconic acid on reaction with
Tollens' reagent.
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