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Q.1
The most abundant organic molecule is ... ... [ CPMT 1999 ]
0%
a) RUBISCO
0%
b) Starch
0%
c) Cellulose
0%
d) Chitin
Explanation
Cellulose is the most abundant organic compound on Earth. It is the main constituent of plant fiber; plants contain on average 33% cellulose, and cotton is the purest form at 90%. Cellulose is a linear polymer of as many as 10,000 D-glucose units. Answer : (c)
Q.2
Which one is not an essential amino acid ? .... ... [ AFMC 2002]
0%
a) Leucine
0%
b) Lysine
0%
c) Methionine
0%
d) Alanine
Explanation
Alanine is a non-essential amino acid made in the body from either the conversion of the carbohydrate pyruvate or the breakdown of DNA and the dipeptides carnosine and anserine Answer : (d)
Q.3
Chitin occurs in the wall of ... .. [ Odisha 2004]
0%
a) Bacteria
0%
b) Algae
0%
c) Fungi
0%
d) Yeast
Explanation
Chitin, which occurs in nature as ordered macrofibrils, is the major structural component in the exoskeletons of the crustaceans, crabs and shrimps, as well as the cell walls of fungi. Answer : (c)
Q.4
The basic/structural unit of a nucleic acid is .... .... [ WB 2010]
0%
a) Pentose sugar
0%
b) Nucleoid
0%
c) Nucleoside
0%
d) Nucleotide
Explanation
The basic repeating unit of nucleic acids are known as nucleotides. Answer : (d)
Q.5
Which one is water soluble vitamin? .... .... [ kerala 2007]
0%
a) Vitamine A
0%
b) Vitamine B
0%
c) Vitamine D
0%
d) Vitamine E
Explanation
The water-soluble vitamins include ascorbic acid (vitamin C), thiamin, riboflavin, niacin, vitamin B6 (pyridoxine, pyridoxal, and pyridoxamine), folacin, vitamin B12, biotin, and pantothenic acid. Answer : (b)
Q.6
Enzyme activity is facilitated through ... ..... [ kerala 2000 ]
0%
a) Reduction in activation energy
0%
b) Increase in activation energy
0%
c) Altering pH
0%
d) Altering temperature
Explanation
The enzyme-substrate complex lower activation energy by bending substrate molecules in a way that facilitates bond-breaking, helping to reach the transition state. Answer : (a)
Q.7
Feedback inhibition of enzyme is influenced by . .... ... [ AIIMS 1997]
0%
a) Enzyme
0%
b) External factors
0%
c) End product
0%
d) Substrate
Explanation
Feedback inhibition is a cellular control mechanism in which an enzyme's activity is inhibited by the enzyme's end product. This mechanism allows cells to regulate how much of an enzyme’s end product is produced. Answer : (c)
Q.8
Enzymes are sensitive to ... ... [ B.V. 2002]
0%
a) Cold
0%
b) Cell wall
0%
c) Heat
0%
d) Pressure
Explanation
Enzyme activity can be affected by a variety of factors, such as temperature, pH, and concentration. Enzymes work best within specific temperature and pH ranges, and sub-optimal conditions can cause an enzyme to lose its ability to bind to a substrate Answer : (c)
Q.9
Enzymes which catalyse reactions involving changes in structure of a molecule are ... ...
0%
a) Ligases
0%
b) Isomerases
0%
c) Hydrolases
0%
d) Transferases
Explanation
Isomerases are a general class of enzymes that convert a molecule from one isomer to another. Isomerases facilitate intramolecular rearrangements in which bonds are broken and formed. i.e. changes in structure Ligases are enzymes that are capable of catalyzing the reaction of joining two large molecules by establishing a new chemical bond. Hydrolases are enzymes that catalyze the cleavage of a covalent bond using water. Types of hydrolase include esterases, such as phosphatases, that act on ester bonds, and proteases or peptidases that act on amide bonds in peptides. Transferases are enzymes that catalyze the transfer of a group of atoms, such as amine, carboxyl, carbonyl, methyl, acyl, glycosyl, and phosphoryl from a donor substrate to an acceptor compound. Answer : (b)
Q.10
The lock and key principle is related to ... ..... [ MPPMT 2010]
0%
a) Dark reaction
0%
b) Enzyme action
0%
c) Chemical action
0%
d) Hormonal action
Explanation
The specific action of an enzyme with a single substrate can be explained using a Lock and Key analogy first postulated in 1894 by Emil Fischer. Answer : (b)
Q.11
Combination of apoenzyme and coenzyme produces ... ... [ AIIMS 1992]
0%
a) Prosthetic group
0%
b) Holoenzyme
0%
c) Enzyme-substrate complex
0%
d) Enzyme-product complex
Explanation
An apoenzyme is an inactive enzyme, activation of the enzyme occurs upon binding of an organic or inorganic cofactor. Coenzymes are organic nonprotein molecules that bind with the protein molecule (apoenzyme) to form the active enzyme (holoenzyme). The combination of the apoenzyme and the coenzyme results in the formation of a functional enzyme which is called holoenzyme. Answer : (b)
Q.12
CH3(CH2)7CH=CH(CH2)7 .COOH is .... ....[ Har PMT 2002]
0%
a) Linolenic acid
0%
b) Oxalosuccinate
0%
c) Oleic acid
0%
d) α - ketoglutarate
Explanation
Formula: C18H34O2 Answer : (c)
Q.13
Middle lamella mainly contains ... ... [AMU 2011]
0%
a) Ca and Mg
0%
b) Ca only
0%
c) K
0%
d) Na
Explanation
The middle lamella is a layer which cements the cell walls of two adjoining plant cells together. The middle lamella is made up of calcium and magnesium pectates. Answer : (a)
Q.14
Which is mismatched ... ... [ kerala 2007]
0%
a) Agar - Polymer of glucose and sulphur containing carbohydrates
0%
b) Chitin - Polymer of glycosamine
0%
c) Lipopolysaccharides - A complex of lipid and polysaccharide
0%
d) Glycogen - Polymer of glucose
Explanation
agar is a polymer of galactose Answer : (a)
Q.15
Expand ELISA ... .... [ DPMT 2007]
0%
a) Enzyme linked inductive assay
0%
b) Enzyme linked ion sorbent assay
0%
c) Enzyme linked immunosorbent assay
0%
d) None of the above
Explanation
ELISA: Enzyme-linked immunosorbent assay ELISA is a rapid immunochemical test that involves an enzyme used for measuring a wide variety of tests of body fluids. ELISA tests detect substances that have antigenic properties, primarily proteins rather than small molecules and ions, such as glucose and potassium Answer : (c)
Q.16
Positive Coiling of DNA duplex is ... ..... [ MPPMT 2000 ]
0%
a) Left hand
0%
b) Right handed
0%
c) Parallel
0%
d) All the above
Explanation
Positive supercoiling is the right-handed, coiling of DNA thus winding occurs in the clockwise direction. Answer : (b)
Q.17
One of the following is without coenzyme activity ... ... [ CPMT 1992]
0%
a) Vitamin E
0%
b) Thiamine
0%
c) Biotin
0%
d) Riboflavin
Explanation
The active coenzyme form of thiamin, vitamin B1, is thiamin pyrophosphate (TPP) Biotin is a coenzyme for multiple carboxylase enzymes. The active forms of riboflavin, vitamin B2, are the coenzymes flavin mononucleotide Answer : (a)
Q.18
Holoenzyme is .... ... [ AMU 1999 ]
0%
a) Protein moiety of enzyme
0%
b) Non-protein moiety of enzyme
0%
c) Complete enzyme
0%
d) Inactive enzyme
Explanation
Holoenzyme a biochemically active compound formed by the combination of an enzyme with a coenzyme. Answer : (c)
Q.19
Cholesterol is ... ... [ Odisha 2008]
0%
a) Monosaccharide
0%
b) Protein
0%
c) Sterol
0%
d) Wax
Explanation
Sterols, also known as steroid alcohols, are a subgroup of the steroids and an important class of organic molecules. They are a type of lipid. The most familiar type of animal sterol is cholesterol, which is vital to cell membrane structure, and functions as a precursor to fat-soluble vitamins and steroid hormones Answer : (c)
Q.20
Double hydrogen bond occurs in DNA between ... ... [ CPMT 2008]
0%
a) Adenine and thymine
0%
b) Uracil and thymine
0%
c) Adenine and guanine
0%
d) Thymine and cytosine
Explanation
In the DNA helix, the bases: adenine, cytosine, thymine and guanine are each linked with their complementary base by hydrogen bonding. Adenine pairs with thymine with 2 hydrogen bonds. Guanine pairs with cytosine with 3 hydrogen bonds. Answer : (a)
Q.21
Natural anticoagulant is .... ... [ AMU 2005]
0%
a) Serotonin
0%
b) Digitonin
0%
c) Heparin
0%
d) Erythromycin
Explanation
Heparin is an anticoagulant (blood thinner) that prevents the formation of blood clots. Heparin does not break down clots that have already formed (unlike tissue plasminogen activator) but allows fibrinolysis to work normally to break down clots. Heparin is used to treat and prevent blood clots in the veins, arteries, or lung. Heparin is also used before surgery to reduce the risk of blood clots. Answer : (c)
Q.22
Coenzymes FMN and FAD are derived from vitamin .... ..... [ AFMC 1997]
0%
a) C
0%
b) B6
0%
c) B1
0%
d) B2
Explanation
Riboflavin (Vitamin B2) is the precursor of two coenzymes known as flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). Answer : (d)
Q.23
Structure of protein insulin was first studied by .... ... [ AFMC 2004 ]
0%
a) Sanger
0%
b) Stanley
0%
c) Nicholson
0%
d) Watson
Explanation
The structure of protein insulin was first studied by Sanger. It consists of two polypeptide chains which are linked by the disulphide bonds. Answer : (a)
Q.24
Immediate source of energy is ... ... [ Chd CET 1997]
0%
a) Sucrose
0%
b) Glucose
0%
c) Fat
0%
d) Starch
Explanation
The immediate source of energy for most cells is glucose. But glucose is not the only fuel on which cells depend. Answer : (b)
Q.25
Non-protein part of enzyme is called ... ..... [ HPPMT 2007]
0%
a) Prosthetic group
0%
b) Active site
0%
c) Cofactor
0%
d) Catalytic agent
Explanation
Cofactor: The first type of enzyme partner is a group called cofactors, or molecules that increase the rate of reaction or are required for enzyme function. Coenzymes A specific type of cofactor, coenzymes, are organic molecules that bind to enzymes and help them function. The key here is that they're organic. Prosthetic Groups: Prosthetic groups are cofactors that bind tightly to proteins or enzymes. As if holding on for dear life, they are not easily removed. Answer : (c)
Q.26
Osmotically inactive chief stored material in animal body is .... .... [ BHU 2002]
0%
a) Protein
0%
b) Phosphogen
0%
c) Lipid
0%
d) Glycogen
Explanation
Glycogen is a polysaccharide that is the principal storage form of glucose (Glc) in animal and human cells. Glycogen is a sparsely soluble (and therefore osmotically inactive) branched polyssacharide, composed of glucose monomers joined through glycosidic bonds. Answer : (d)
Q.27
RNA takes part in synthesis of ... ... [ CPMT 1991]
0%
a) DNA
0%
b) Carbohydrate
0%
c) Fat
0%
d) Protein
Explanation
In the synthesis of protein, three types of RNA are required. ribosomal RNA (rRNA), transfer RNA (tRNA) and messenger RNA (mRNA) Answer : (d)
Q.28
The stored food material found in muscles is .... .... [ MPPMT 1999 ]
0%
a) Protein
0%
b) Glycogen
0%
c) Lipid
0%
d) Phosphogen
Explanation
Glycogen stores in skeletal muscle serve as a form of energy storage for the muscle itself; however, the breakdown of muscle glycogen impedes muscle glucose uptake from the blood, thereby increasing the amount of blood glucose available for use in other tissues. Answer : (b)
Q.29
Which one is essential fatty acid .... .... [ BHU 2008]
0%
a) Linoleic acid
0%
b) Lauric acid
0%
c) Arachidonic acid
0%
d) All the above
Explanation
The three main omega-3 fatty acids are alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) Saturated Fatty Acids examples: Lauric acid, myristic acid, palmitic acid, Stearic acid, Arachidic acid Unsaturated Fatty Acids examples: Palmitoleic acid, Oleic acid, Linoleic acid, myristoleic acid, Answer : (d)
Q.30
Principal organic constituent of a living being in order of relative abundance is ... .... [ JKCMEE 1992]
0%
a) Water
0%
b) Protein
0%
c) Lipid
0%
d) DNA
Explanation
Component
% of the total cellular mass
Water
70-90
Proteins
10-15
Lipids
2
Carbohydrates;
3
Mucleic acids
5-7
Ions
1
Average Composition of Cells Principal organic constituent of a living being in order of relative abundance is Proteins Answer : (b)
Q.31
Inulin is a polymer of ... ... [ WB 2011]
0%
a) Glucose
0%
b) Galactose
0%
c) Fructose
0%
d) Arabinose
Explanation
Inulin is a heterogeneous collection of fructose polymers Answer : (c)
Q.32
Amino acids are produced from ... ... [ CBSE 1992]
0%
a) Proteins
0%
b) Fatty acids
0%
c) Essential oils
0%
d) α-keto acids
Explanation
Amino acids are organic compounds containing an amino group and an acidic group as substituents on the same carbon i.e., the α-carbon. Most amino acids are synthesized from α-ketoacids, and later transaminated from another amino acid, usually glutamate. A "transamination reaction", in which an amino group is transferred from an amino acid to the a-carbon of a ketoacid, is catalyzed by an aminotransferase Answer : (d)
Q.33
atch the column .... ..[ KCET 2004]
a) Starch
p) Protein synthesis
b) Haemoglobin
q) Sex hormone
c) RNA
r) Storage product
d) Steroid
s) Transport of gases
0%
a) a - r, b - p, c - s, d - q
0%
b) a- r, b - s, c - p, d - q
0%
c) a - s, b - r, c - p, d - q
0%
d) a - r, b - s, c - q, d - p
Explanation
Starch Storage product, a- r Haemoglobin Transport of gases, b - s RNA Protein synthesis, c - p Steroid Sex hormon, d - q Answer : (b)
Q.34
In blood, the main buffers are ... ... [ BHU 1990]
0%
a) Na and K
0%
b) Sodium dihydrogen phosphate and sodium monohydrogen phosphate
0%
c) Carbonic acid and bicarbonate
0%
d) Ammonium acetate
Explanation
Human blood contains a buffer of carbonic acid (H2CO3) and bicarbonate anion (HCO3-) in order to maintain blood pH between 7.35 and 7.45 Answer : (c)
Q.35
Name the most abundant elements which occur in nucleic acid macromolecules ... ... [ WB 2007]
0%
a) C, H, O, N, S
0%
b) C, O, N, S
0%
c) C, O, P, S
0%
d) C, H, O, N, P
Explanation
Nucleic acids contain the same elements as proteins: carbon, hydrogen, oxygen, nitrogen; plus phosphorous (C, H, O, N, and P) Answer : (d)
Q.36
Rayon and cellophane are forms of ... ...
0%
a) Cellulose xanthate
0%
b) Cellulose nitrate
0%
c) Cellulose acetate
0%
d) Carboxymethyl cellulose
Explanation
Cellulose xanthate is a compound produced from cellulose in the viscose process for making rayon. Answer : (a)
Q.37
Element located in centre of porphyrin ring of chlorophyll is .... ..... [ CBSE 2003]
0%
a) Potassium
0%
b) Manganese
0%
c) Magnesium
0%
d) Calcium
Explanation
Magnesium is the element located-in centre of porphyrin ring of chlorophyll Answer : (c)
Q.38
Plant cell wall mainly consists of ... .... [ CPMT 1995]
0%
a) Cellulose
0%
b) Protein
0%
c) Starch
0%
d) None of the above
Explanation
Plant cell walls are primarily made of strong fibers of the carbohydrate polymer cellulose Answer : (a)
Q.39
Km value is related to ... ... [ RPMT 2000 ]
0%
a) Chromatography
0%
b) ES complex
0%
c) ABO complex
0%
d) Morphometry
Explanation
Each enzyme (E) has a substrate (S) binding site in its molecule so that a highly reactive enzyme-substrate complex (ES) is produced. Km is a measure of the affinity an enzyme has for its substrate, as a lower Km means that less of the substrate is required to reach half of Vmax. Answer : (b)
Q.40
Starch is insoluble, yet it accumulates in large quantity in Potato tuber because ... .... [ CPMT 2004]
0%
a) Storage product should be insoluble
0%
b) Starch is synthesised in tubers
0%
c) Tubers respire slowly
0%
d) Translocated sucrose in polymerised here
Explanation
The stored starch is used by the tubers during unfavourable condition like dormancy. Starch is formed by a-1,4 linkages between two glucose unit which is broken down during its digestion. It is storage food material of plant cells. Answer : (a)
Q.41
Which one consists of essential amino acids? .... ... [RPMT 1998]
0%
a) Tryptophan and Glutamic acid
0%
b) Lysine and Phenylalanine
0%
c) Leucine and Glycine
0%
d) Valine and tyrosine.
Explanation
The 9 essential amino acids are: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine Answer : (b)
Q.42
Holoenzyme is produced by ... ... [ Odisha 2009]
0%
a) Combined coenzyme and apoenzyme
0%
b) Only prosthetic group
0%
c) Only protein
0%
d) Only cofactor
Explanation
Holoenzyme is produced by a biochemically active compound formed by the combination of an enzyme with a coenzyme. Answer : (a)
Q.43
Which of the following lipid is essential part of good diet? ... .... [ CBSE 1999 ]
0%
a) Oleic acid
0%
b) Linoleic acid
0%
c) Stearic acid
0%
d) Palmitic acid
Explanation
Lipids also encompass molecules such as fatty acids. Linoleic acid is classified as an essential nutrient, since the body requires it but cannot synthesize it. Other essential fatty acids are eicosapentaenoic acid, gamma-linolenic acid, dihomo-gamma-linolenic acid or arachidonic acid or AA Answer : (b)
Q.44
A reagent added to a sample shows change of colour from green to yellow. it is due to presence of reducing sugar. The test is ... ... [ Manipal 2002]
0%
a) Elisa test for detecting AIDS
0%
b) Benedict's test for detecting glucosuria
0%
c) Fehling's test for detecting hyperglycemia
0%
d) Ninhydrin test for detecting glucosidic linkage
Explanation
Benedict's reagent can also be used to test for the presence of glucose in urine, elevated levels of which is known as glucosuria. Substance in water + 3 mL Benedict's solution → then boil for few minutes and allow to cool. → Red, green, or yellow precipitate is obtained Reducing sugar, such as glucose, is present Substance in water + 3 mL Benedict's solution → then boil for few minutes and allow to cool → Solution remains clear or is a little blue Reducing sugar is not present Answer : (b)
Q.45
Which one is a carbohydrate ... ... [ CMC 1992]
0%
a) Glycerol
0%
b) Maltase
0%
c) Sucrose
0%
d) All the above
Explanation
They contain hydrogen and oxygen in the same ratio as water (2:1) Sucrose formula: C12H22O11 Maltase is a enzyme that catalyzes the hydrolysis of the disaccharide maltose to the simple sugar glucose Glycerol formula: C3H8O3 Answer : (c)
Q.46
Which one is glucose? ... .... [ Odisha 2007]
0%
a) C3H8O3
0%
b) C6H12O6
0%
c) C55H70O6
0%
d) C6H10O6
Explanation
Glucose formula: C6H12O6 Answer : (b)
Q.47
Unsaturated fatty acids have .... ... [ AMU 2002]
0%
a) Oleic acid
0%
b) High melting point
0%
c) One or more double bonds
0%
d) Palmitic acid
Explanation
A fat molecule is mono-unsaturated if it contains one double bond, and poly-unsaturated if it contains more than one double bond. Answer : (c)
Q.48
The activity of succinate dehydrogenase is inhibited by ... .... [ AMU 1992]
0%
a) Malonate
0%
b) Pyruvate
0%
c) Glycolate
0%
d) Phosphoglycerate
Explanation
Malonate is a competitive inhibitor of the enzyme succinate dehydrogenase: malonate binds to the active site of the enzyme without reacting, and so competes with succinate, the usual substrate of the enzyme. Malonate resembles the substrate succinate, without a −CH2CH2− group required for dehydrogenation Answer : (a)
Q.49
Calmodulin is ... .. [ DPMT 2001]
0%
a) Carotene binding protein
0%
b) Cadmium binding protein
0%
c) Calcium binding protein
0%
d) Chlorophyll binding protein
Explanation
Calmodulin (CaM) is a multifunctional intermediate calcium-binding messenger protein expressed in all eukaryotic cells. Answer : (c)
Q.50
Select the correct answer from the following for DNA can be ... ...[ BHU 2008] 1) A-DNA 2) B-DNA 3) Z-DNA 4) Y-DNA
0%
a) 1, 2 and 3 correct
0%
b) 1 and 2 correct
0%
c) 2 and 4 correct
0%
d) 1 and 3 correct
Explanation
Three biologically active double helical structures are A-DNA, B-DNA and Z-DNA. Answer : (a)
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