iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Identify the basic amino acid from the
following
A.
Valine
B.
Lysine
C.
Tyrosine
D.
Glutamic Acid
Correct Answer: B
Explanation:
Glutamic Acid - is an acidic amino acid.
Lysine - is a basic amino acid.
Valine - is an aliphatic amino acid.
Tyrosine - is an aromatic amino acid.
2019
Q52
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Consider the following statements :
(A) Coenzyme of metal ion that is tightly bound to enzyme protein is called prosthetic group.
(B) A complete catalytic active enzyme with its bound prosthetic group is called apoenzyme
Select the correct option
A.
Both (A) and (B) are false
B.
(A) is false but (B) is true
C.
Both (A) and (B) are true
D.
(A) is true but (B) is false
Correct Answer: D
Explanation:
Coenzyme or metal ion that is tightly bound to enzyme protein is called prosthetic group while a complete catalytic active enzyme with its bound prosthetic group is called holoenzyme.
2019
Q53
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Concanavalin A is :
A.
a lectin
B.
a pigment
C.
an alkaloid
D.
an essential oil
Correct Answer: A
Explanation:
Concanavalin A is an example of lection.
2018
Q54
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
The two functional groups characteristic of
sugars are
A.
carbonyl and methyl
B.
carbonyl and hydroxyl.
C.
hydroxyl and methyl
D.
carbonyl and phosphate
Correct Answer: B
Explanation:
Sugar is a carbohydrate. These are
polyhydroxy aldehyde, ketone or their
derivatives, which means they have
carbonyl and hydroxyl groups in its
structure.
2017
Q55
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which of the following statements is correct with reference to enzymes?
A.
Holoenzyme = Apoenzyme + Coenzyme
B.
Coenzyme = Apoenzyme + Holoenzyme
C.
Holoenzyme = Coenzyme + Co-factor
D.
Apoenzyme = Holoenzyme + Coenzyme
Correct Answer: A
Explanation:
Holoenzyme is the complete conjugate
enzyme consisting of an apoenzyme and a cofactor.
Cofactor may be organic or inorganic in nature.
Organic cofactors are of two types-coenzyme and
prosthetic group.
2017
Q56
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which of the following are not polymeric?
A.
Proteins
B.
Polysaccharides
C.
Lipids
D.
Nucleic acids
Correct Answer: C
Explanation:
– Nucleic acids are polymers of
nucleotides
– Proteins are polymers of amino acids
– Polysaccharides are polymers of
monosaccharides
– Lipids are the tri-esters of fatty acids
with glycerol.
2016
Q57
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
A non-proteinaceous enzyme is
A.
Iysozyme
B.
ribozyme
C.
ligase
D.
deoxyribonuclease.
Correct Answer: B
Explanation:
A ribozyme is a ribonucleic acid (RNA)
enzyme that catalyses a chemical reaction in a similar
way to that of a protein enzyme. These are found in
ribosomes and are also called catalytic RNAs.
2016
Q58
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which of the following is the least likely to be involved in stablishing the three-dimensional folding of most proteins?
A.
Hydrogen bonds
B.
Electrostatic interaction
C.
Hydrophobic interaction
D.
Ester bonds
Correct Answer: D
Explanation:
Tertiary structure or three dimensional
structure of protein is stabilised by several types of
bonds—hydrogen bonds, ionic bonds, van der Waal’s
interactions, covalent bonds and hydrophobic bonds.
2016
Q59
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which of the following describes the given graph correctly?
A.
Endothermic reaction with energy A in presence of enzyme and B in absence of enzyme.
B.
Exothermic reaction with energy A in presence of enzyme and B in absence of enzyme.
C.
Endothermic reaction with energy A in absence of enzyme and B in presence of enzyme.
D.
Exothermic reaction with energy A in absence of enzyme and B in presence of enzyme.
Correct Answer: B
Explanation:
The graph shows the activation energies
of catalyzed and uncatalyzed reations. A
transition state is observed when the reactants
are at the crest of the hump. At this state,
they are ready to be converted to products.
If the products are at a lower level than the
reactants, the reaction is exothermic.
2016
Q60
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which one of the following statements is wrong?
A.
Uracil is a pyrimidine.
B.
Glycine is a sulphur containing amino acid.
C.
Sucrose is a disaccharide.
D.
Cellulose is a polysaccharide.
Correct Answer: B
Explanation:
Glycine (abbreviated as Gly or G) is the
smallest of the 20 amino acids commonly
found in proteins, and indeed is the smallest
possible (having a hydrogen substituent as its
side-chain). The formula is NH2CH2COOH.
Its codons are GGU, GGC, GGA, GGG of
the genetic code.
2016
Q61
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
A typical fat molecule is made up of
A.
one glycerol and one fatty acid molecule
B.
three glycerol and three fatty acid molecules
C.
three glycerol molecules and one fatty acid molecule
D.
one glycerol and three fatty acid molecules.
Correct Answer: D
Explanation:
Neutral or true fats are triglycerides which
are formed by esterification of three molecules of fatty
acids with one molecule of trihydric alcohol, glycerol
(glycerine or trihydroxy propane).
2015
Q62
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
The chitinous exoskeleton of arthropods is formed by the polymerisation of
A.
N - acetyl glucosamine
B.
lipoglycans
C.
keratin sulphate and chondrotin sulphate
D.
D - glucosamine.
Correct Answer: A
Explanation:
Chitin is a structural polysaccharide that
constitutes the exoskeleton of arthropods. It is a
complex carbohydrate in which N-acetyl glucosamine
monomers are joined together by (1, 4) $\beta $-linkages.
Chitinous exoskeleton provides strength and elasticity
to arthropods.
2015
Q63
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which of the following biomolecules does have a phosphodiester bond?
A.
Amino acids in a polypeptide
B.
Nucleic acids in a nucleotide
C.
Fatty acids in a diglyceride
D.
Monosaccharides in a polysaccharide
Correct Answer: B
Explanation:
Nucleic acids have phophodiester bond
in a nucleotide.
2015
Q64
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which one of the following statements is incorrect?
A.
The compettive inhibitor does not affect the rate of breakdown of the enzyme -substrate complex.
B.
The presence of the competitive inhibitor decreases the Km of the enzyme for the substrate
C.
A competitive inhibitor reacts reversibly with the enzyme to form and enzyme-inhibitor complex.
D.
In competitive inhibition, the inhibitor molecules is not chemically changed by the enzyme.
Correct Answer: B
Explanation:
Competitive inhibition is a reversible
inhibition where inhibitor competes with the normal
substrate for the active site of enzyme. A competitive
inhibitor is usually chemically similar to the normal
substrate and therefore, fits into the active site of an
enzyme and binds with it. The inhibition is thus due
to substrate analogue. The enzyme, now cannot act
upon the substrate and reaction products are not
formed. E.g., the activity of succinate dehydrogenase
is inhibited by malonate. Km value or Michaelis constant is defined as the substrate concentration at
which half of the enzyme molecules are forming
enzyme substrate (ES) complex or concentration of
the substrate when the velocity of the enzyme reaction
is half the maximal possible. A smaller Km value
indicates greater affinity of the enzyme for its
substrate, hence, shows a quicker reaction. The
competitive inhibitor decreases the affinity of enzyme
for substrate, thus increases the Km value.
2014
Q65
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which one of the following is a non - reducing carbohydrate?
A.
Maltose
B.
Sucrose
C.
Lactose
D.
Ribose 5-phosphate
Correct Answer: B
Explanation:
Sucrose is classified under non reducing
sugars because it does not have any free
aldehyde or keto group.
2014
Q66
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Select the option which is not correct with respect to enzyme action.
A.
Substrate binds with enzyme at its active site.
B.
Addition of lot of succinate does not reverse the inhibition of succinic dehydrogenase by malonate.
C.
A non-competitive inhibitor binds the enzyme at a site distinct from that which binds the substrate.
D.
Malonate is a competitive inhibitor of succinic dehydrogenase.
Correct Answer: B
Explanation:
Inhibitions of succinic dehydrogenase
by malonate is an example of competitive
inhibition. Thus it is a reversible reaction.
On increasing the substrate (succinate)
concentration the effect of inhibitor is
removed and Vmax remains same.
2013
Q67
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
The figure shows a hypothetical tetrapeptide portion of a protein with parts labelled A - D. Which one of the following options is correct?
A.
D is not acidic amino acid-glutamic acid.
B.
C is an aromatic amino acid-tryptophan.
C.
A is the C-terminal amino acid and D is N-terminal amino acid.
D.
A is a sulpur containing amino acid methionine.
Correct Answer: A
Explanation:
Glutamic acid and aspartic acid are
acidic amino acids with two carboxylic groups
and one amino group.
2013
Q68
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which of the following statements about enzymes is wrong?
A.
Enzymes are denaturated at high temperatures.
B.
Enzymes are mostly proteins but some are lipids also.
C.
Enzymes are highly specific.
D.
Enzymes require optimum pH and temperature for maximum activity.
Correct Answer: B
Explanation:
Almost all enzymes are proteins. There
are some nucleic acids that behave like
enzymes. There are called ribozyme (also
called RNA enzyme or catalytic RNA).
2013
Q69
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Uridine, present only in RNA is a
A.
nucleoside
B.
nucleotide
C.
purine
D.
pyrimidine.
Correct Answer: A
Explanation:
A nucleoside is pentose sugar and base
together, without the phosphate group. Uracil is
present as uridine in RNA only.
Uracil + Ribose $ \to $ Uridine
2013
Q70
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
A phosphoglyceride is always made up of
A.
a saturated or unsaturated fatty acid esterified to glycerol molecule to which a phosphate group is also attached.
B.
a saturated or unsaturated fatty acid esterified to a phosphate group which is also attached to a glycerol molecule.
C.
only a saturated fatty acid esterified to a glycerol molecule to which a phosphate group is also attached.
D.
only an unsaturated fatty acid esterified to a glycerol molecule to which a phosphate group is also attached.
Correct Answer: A
Explanation:
Phosphoglycerides are the triesters of fatty
acids (either saturated or unsaturated) and glycerol
to which a phosphate group is also attached.
2013
Q71
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Macromolecule chitin is
A.
sulphur containing polysaccharide
B.
simple polysaccharide
C.
nitrogen containing polysaccharide
D.
phosphorous containing polysaccharide.
Correct Answer: C
Explanation:
Chitin is a structural polysaccharide that
constitutes the exoskeleton of arthropods. It is a
complex carbohydrate in which N-acetyl glucosamine
monomers are joined together by (1, 4) $\beta $-linkages.
Chitinous exoskeleton provides strength and elasticity
to arthropods.
2013
Q72
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Transition state structure of the substrate formed during an enzymatic reaction is
A.
transient and unstable
B.
permanent and stable
C.
transient but stable
D.
permanent but unstable.
Correct Answer: A
Explanation:
Transition state structure formed during
an enzymatic reaction is transient and
unstable.
2013
Q73
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
The essential chemical components of many coenzymes are
A.
carbohydrates
B.
vitamins
C.
proteins
D.
nucleic acids.
Correct Answer: B
Explanation:
The essential chemical components of
many enzymes are vitamins, e.g., coenzyme
nicotinamide adenine dinucleotide (NAD)
and NADP contain vitamin niacin.
2012
Q74
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which one of the following biomolecules is correctly characterized?
A.
Lecithin - a phosphorylated glyceride found in cell membrane.
B.
Palmitic acid - an unsaturated fatty acid with 18 carbon atoms.
C.
Adenylic acid - adenosine with a glucose phosphate molecule.
D.
Alanine amino acid - contains an amino group and an acidic group anywhere in the molecule.
Correct Answer: A
Explanation:
Palmitic acid is one of the most
common, saturated fatty acids found in
animals and plants. It has 16 carbons
including the carboxyl carbon. Adenylic acid
is a nucleotide consisting of adenine, ribose
or deoxyribose, and a phosphate group. It
is a constituent of DNA or RNA. It is also
called adenosine monophosphate. Amino
acids are organic acids (with carboxylic
group COOH) having amino group (–NH2)
generally attached to Carbon or carbon next
to carboxylic group. The carbon also bears a variable alkyl group (R) or hydrogen or
hydrocarbon. In alanine (R) is represented
by methyl group.
2012
Q75
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
The given diagrammatic representation shows one of the caregories of small molecular weight organic compounds in the living tissues. Identify the category shown and the one blank component ''X'' in it.
A.
Category
Component
Cholesterol
Guanine
B.
Category
Component
Amino acid
NH2
C.
Category
Component
Nucleotide
Adenine
D.
Category
Component
Nucleoside
Uracil
Correct Answer: D
Explanation:
The given structure corresponds with the
structure of ribose sugar. As it lacks a phosphoric acid
hence it can be a nucleoside not a nucleotide.
2012
Q76
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which one out of A - D given below correctly represents the structural formula of the basic amino acid?
A.
C
B.
D
C.
A
D.
B
Correct Answer: B
Explanation:
Basic amino acids have an additional amino
group without forming amides thus they are diamino
monocarboxylic acids e.g., arginine, lysine, etc.
2012
Q77
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which one is the most abundant protein in the animal world?
A.
Trypsin
B.
Haemoglobin
C.
Collagen
D.
Insulin
Correct Answer: C
Explanation:
Collagen is an insoluble fibrous protein
found extensively in the connective tissue of skin,
tendons and bone. Collagen accounts for over 30%
of the total body proteins of mammals and it is the
most abundant animal protein.
2012
Q78
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which one of the following is wrong statement?
A.
Anabaena and Nostoc are capable of fixing nitrogen in free-living state also
B.
Root module forming nitrogen fixers live as aerobes under free-living conditions.
C.
Phosphorus is a constituent of cell membrances, certain nucleic acids and all proteins.
D.
Nitrosomonas and Nitrobacter are chemo-autotrophs.
Correct Answer: C
Explanation:
Phosphorus is a constituent of nucleic
acids of both DNA and RNA but absent in
cell membranes and cell proteins.
2011
Q79
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
The curve given below shows enzymatic activity in relation to three conditions (pH, temperature and substrate concentration). What do the two axes (x and y) represent?
A.
x-axis
y-axis
enzymatic activity
pH
B.
x-axis
y-axis
temperature
enzyme activity
C.
x-axis
y-axis
substrate concentration
enzymatic activity
D.
x-axis
y-axis
enzymatic activity
temperature
Correct Answer: B
Explanation:
In the given curve, the relation between
temperature and enzyme activity is shown.
2011
Q80
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which one of the following structural formulae of two organic compounds is correctly identified along with its related function?
A.
B : Adenine - A nucleotide that makes up nucleic acids
B.
A : Triglyceride - Major source of energy
C.
B : Uracil - A component of DNA
D.
A : Lecithin - A component of cell membrane
Correct Answer: D
Explanation:
Lecithin is a fat like substance (a
phospholipid), which is a part of plasma
membrane.
2010
Q81
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
The figure given below shows the conversion of a substate into product by an enzyme. In which one of the four options (a-d) the components of reaction labelled as A, B, C and D are identified correctly?
A.
A
B
C
D
Potential energy
Transition state
Activation energy
Activation energy with out enzyme
B.
A
B
C
D
Transition state
Potential energy
Activation energy without enzyme
Activation energy with enzyme
C.
A
B
C
D
Potential energy
Transition state
Activation energy with enzyme
Activation energy without enzyme
D.
A
B
C
D
Activation energy with enzyme
Transition state
Activation energy without enzyme
Potential energy
Correct Answer: B
2010
Q82
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Three of the following statements about enzymes are correct and one is wrong. Which one is wrong?
A.
Enzymes require optimum pH for maximal activity.
B.
Enzymes are denaturated at high temperature but in certain exceptional organisms they are effective even at temperatures 80o - 90oC.
C.
Enzymes are highly specific.
D.
Most enzymes are proteins but some are lipids.
Correct Answer: D
Explanation:
Enzymes are mostly proteins but some are
RNA (ribozymes). No lipid working as enzymes are
known.
2008
Q83
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Modern detergents contain enzyme preparations of
A.
thermoacidophiles
B.
thermophiles
C.
acidophiles
D.
alkaliphiles.
Correct Answer: D
Explanation:
Modern detergents contain enzyme
preparation of alkaline protease which are called
alkaliphiles, for removing protein stain.
2008
Q84
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
A competitive inhibitor of succinic dehydrogenase is
A.
$\alpha $-ketoglutarate
B.
Malate
C.
malonate
D.
oxaloacetate.
Correct Answer: C
Explanation:
Malonate is a competitive inhibitor of succinic dehydrogenase, which is an enzyme involved in the citric acid cycle. Malonate is structurally similar to succinate, the natural substrate of succinic dehydrogenase. Therefore, malonate can bind to the active site of the enzyme and prevent succinate from binding, which inhibits the enzyme's activity. This leads to a decrease in the production of ATP, which can have a negative impact on cellular respiration.
2008
Q85
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Carbohydrates are commonly found as starch in plants storage organs. Which of the following five properties of starch (1 $-$ 5) make it useful as a storage material?
(1) Easily translocated
(2) Chemically non-reactive
(3) Easily digested by animals
(4) Osmotically inactive
(5) Synthesized during photosynthesis
The useful properties are
A.
(1), (3) and (5)
B.
(1) and (5)
C.
(2) and (3)
D.
(2) and (4).
Correct Answer: D
Explanation:
Carbohydrates are commonly found
as starch in plant storage organs. It is a
chemically non-reactive and osmotically
inactive polysaccharide with a molecular
weight. Carbohydrates perform a vital role in living organisms. Starch and other
polysaccharides serve as energy storage
in plants, particularly in seeds, tubers, etc.
which provide a major energy source for
animals, including humans.
2008
Q86
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Cellulose is the major component of cell walls of
A.
Pseudomonas
B.
Saccharomyces
C.
Pythium
D.
Xanthomonas.
Correct Answer: C
Explanation:
Cellulose is a major component of
cell wall of Pythium. Pythium is a genus of
parasitic Oomycete. Because this group of
organisms were once classified as fungi, they
are sometimes still treated as such. Pythium,
like others in the family Pythiaceae, are
usually characterized by their production
of coenocytic hyphae, hyphae without
separations. Oogonia generally contain
a single oospore. Antheridia contain an
elongated and club shaped antheridium.
2007
Q87
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
About 98 percent of the mas of every living organism is composed of just six elements including carbon, hydrogen, nitrogen, oxygen and
A.
sulphur and magnesium
B.
magnesium and sodium
C.
calcium and phosphorus
D.
phosphorus and sulphur.
Correct Answer: D
Explanation:
Living organisms requires 6 elements in
relatively large amounts. C, H, O, N, P, S. These
elements contribute to the structural organization of
living organisms.
2006
Q88
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
An organic substance bound to an enzyme and essential for its activity is called
A.
isoenzyme
B.
coenzyme
C.
holoenzyme
D.
apoenzyme.
Correct Answer: B
Explanation:
Coenzyme is an organic substance that
enhances the action of an enzyme by binding
with the protein molecule. Holoenzyme is
a biochemically active compound formed
by the combination of an enzyme with a
coenzyme. Apoenzyme is the protein part of
an enzyme to which the coenzyme attaches
to form an active enzyme. Isoenzyme is
one of the several forms of an enzyme that
catalyse the same reaction but differ from
each other in such properties as substrate
affinity and maximum rates of enzyme
substrate reaction.
2005
Q89
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which one of the following statements regarding enzyme inhibition is correct?
A.
Competitive inhibition is seen when a substrate competes with an enzyme for binding to an inhibitor protein.
B.
Competitive inhibition is seen when the substrate and the inhibitor compete for the active site on the enzyme.
C.
Non-competitive inhibition of an enzyme can be overcome by adding large amount of substrate.
D.
Non-competitive inhibitors often bind to the enzyme irreversibly.
Correct Answer: B
Explanation:
In competitive inhibition the inhibitor
resembles the substrate in structure and
hence compete for the active site of the
enzyme.
2005
Q90
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Nucleotides are building blocks of nucleic acids. Each nucleotide is a composite molecule formed by
A.
base-sugar-phosphate
B.
base-sugar-OH
C.
(base-sugar-phosphate)
D.
sugar-phosphate
Correct Answer: A
Explanation:
Each nucleotide consists of three distinct
units - a phosphate group derived from phosphoric
acid, a pentose sugar and a ring shaped nitrogenous
base.
Nucleoside + Phosphoric acid $ \to $ Nucleotide + H2O
2005
Q91
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Enzymes, vitamins and hormones can be classified into a single category of biological chemicals, because all of these
A.
help in regulating metabolism
B.
are exclusively synthesized in the body of a living organism as at present
C.
are conjugated proteins
D.
enhance oxidative metabolism.
Correct Answer: A
Explanation:
The major life processes are controlled
by enzymes as they enhance the rate of
biological reactions.
Vitamins are required in limited
amounts by organisms for regulation of
metabolism and growth.
Hormones are organic compounds
produced by certain organs in small
quantities. They act physiologically far from
their site of origin.
2005
Q92
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
The catalytic efficiency of two different enzymes can be compared by the
A.
formation of the product
B.
pH of optimum value
C.
Km value
D.
molecular size of the enzyme.
Correct Answer: C
Explanation:
Km (Michealis Menten constant). It is
defined as that substrate concentration at
which, under optimum conditions, the rate
of an enzyme catalysed reaction reaches
half the maximum rate. Km is inversely
proportional to affinity of enzyme far its
substrate.
2005
Q93
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which of the following is the simplest amino acid?
A.
Alanine
B.
Asparagine
C.
Glycine
D.
Tyrosine
Correct Answer: C
Explanation:
Glycine is considered as the simplest amino
acid as it has one amino group, one carboxylic group
and no substituent functional group.
2005
Q94
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Carbohydrates, the most abundant biomolescule on earth, are produced by
A.
some bacteria, algae and green plant cells
B.
fungi, algae and green plant cells
C.
all bacteria, fungi and algae
D.
viruses, fungi and bacteria.
Correct Answer: A
Explanation:
Some bacteria (such as
Rhodopseudomonas), algae and green plants
cell produce carbohydrates.
2004
Q95
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which one of the following enzymes, is copper necessarily associated as an activator?
A.
Carbonic anhydrase
B.
Tryptophanase
C.
Lactic dehydrogenase
D.
Tyrosinase
Correct Answer: D
Explanation:
Copper is associated as an activator with
tyrosinase. It is widely distributed in plants, animals
and man. It is also known as polyphenol oxidase or
catecholase. It oxidizes tyrosine to melanin in
mammals and causes the cut surfaces of many fruits
and vegetable to darken.
2003
Q96
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
The major role of minor elements inside living organisms is to act as
A.
co-factors of enzymes
B.
building blocks of important amino acids
C.
constituent of hormones
D.
binder of cell structure.
Correct Answer: A
Explanation:
Minor elements are those which are
required by plants in very small amounts.
These elements have a significant role
in enzyme activities (zinc activates
carboxylases, carbonic anhydrase and
various dehydrogenases).
2002
Q97
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Lipids are insoluble in water because lipid molecules are
A.
hydrophilic
B.
hydrophobic
C.
neutral
D.
zwitter ions.
Correct Answer: B
Explanation:
Water attracting molecules are called
hydrophilic. Water repelling molecules
are called hydrophobic. Amino acids simultaneously carry positive and negative
charges. Such substances are called zwitter
ions. Lipids are compounds of C, H, O
but the ratio of H and O is more than 2 :
1, that is, the ratio of oxygen is lesser than
carbohydrates. Lipids are insoluble in water
but soluble in non-polar solvents such as
benzene, chloroform etc.
The most common lipid found in a cell
is phospholipid. It contains a hydrophilic
(polar) head and a hydrophobic (non- polar
tail).
2002
Q98
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which of the following is a reducing sugar?
A.
Galactose
B.
Gluconic acid
C.
$\beta $-methyl galactoside
D.
Sucrose
Correct Answer: A
Explanation:
All those sugars which have free aldehyde
or ketone group are called reducing sugars. These are
able to reduce cupric ions (Cu+2) into cuprous ions
(Cu+). Sucrose, starch are non-reducing sugars.
2001
Q99
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Enzyme first used for nitrogen fixation
A.
nitrogenaase
B.
nitroreductase
C.
transferase
D.
transaminase
Correct Answer: A
Explanation:
Nitrogen fixation involves conversion of
atmospheric nitrogen to ammonia. It is done with the
help of nitrogenase enzyme which occurs inside thick
walled heterocysts of the blue green algae. These
provide suitable anaerobic environment for
nitrogenase activity even in aerobic conditions.
2000
Q100
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 7282610 Mar 2026
Which of the following have carbohydrate as prosthetic group?
A.
Glycoprotein
B.
Chromoprotein
C.
Lipoprotein
D.
Nucleoprotein
Correct Answer: A
Explanation:
Glycoproteins are proteins that contain
sugars like carbohydrates as prosthetic group. In most
glycoproteins, the linkage is between asparagine and
N-acetyl-D-glucosamine. Some glycoproteins are
immunoglobulins, membrane proteins and muscle
proteins. Lipoproteins are protein complexed with
lipids like triglycerides, phospholipids etc.
Nucleoproteins are proteins associated with nucleic
acids and chromoproteins are proteins associated with
pigments e.g., cytochrome, phytochrome.
