Biomolecules Biology Important Questions and Answers for NEET

Class 11 Biology Chapter 9 Biomolecules Most important questions answers with FREE PDF are the most important part of all competitive medical entrance exam like NEET, AIIMS, JIPMER and other Board exam of Class 11th.

1 A non reducing sugar is
(A) glucose
(B) sucrose
(C) fructose
(D) maltose

Answer: sucrose
2 Which one is basic amino acid?
(A) proline
(B) arginine
(C) proline
(D) histidine

Answer: arginine
3 Which of the following protein has storage capacity?
(A) glutenins
(B) myosin
(C) chondrin
(D) keratin

Answer: glutenins
4 Sweetest sugar is
(A) frucose
(B) glucose
(C) mannose
(D) lactose

Answer: frucose
5 Which one of the following is a reducing sugar?
(A) galactose
(B) gluconic acid
(C) sucrose
(D) b methyl galctoside

Answer: galactose
6 An organic substance bound to an enzyme and essential for its activity is called
(A) isoenzyme
(B) coenzyme
(C) holoenzyme
(D) apoenzyme

Answer:coenzyme
7 Which of the following mineral element facilitates insulin binding to cell receptor site?
(A) Zinc
(B) Selenium
(C) Copper
(D) Chromium

Answer: Chromium
8 Which of the following is a folate analog?
(A) Methotrexate
(B) Carnosine
(C) Azaserine
(D) Aniserine

Answer: Methotrexate
9 Histamine is a potent secretagogue of
(A) Amylase by the salivary gland
(B) HCI by the stomach
(C) Gastrin by the stomach
(D) NAHCO3 by the pancreas

Answer: HCI by the stomach
10 The contraluminal plasma membrane of small intestinal epithelial cells contain
(A) Disaccharidases
(B) Aminopeptidases
(C) GLUT 5
(D) Na+/ K+ ATPase

Answer: Na+/ K+ ATPase
11 Name the simplest amino acid
(A) Alanine
(B) Tyrosine
(C) Asparagine
(D) Glycine

Answer:Glycine
12 Mineral associated with cytochrome is
(A) Mg
(B) Cu and Ag
(C) Fe
(D) Cu

Answer:Fe
13 The most common secondary structure of proteins is
(A) β-pleated sheet
(B) β-pleated sheet parallel
(C) β-pleated sheet non-parallel
(D) α-helix

Answer: α-helix
14 The term enzyme was coined by
(A) Urey Miller
(B) Pasteur
(C) Kuhne
(D) Buchner

Answer: Kuhne
15 β-oxidation occurs in
(A) Nucleus
(B) Cytoplasm
(C) Mitochondria
(D) Chloroplast

Answer: Mitochondria
16 Koshland’s theory of enzyme action is known as
(A) Lock and key theory
(B) Reduced fit theory
(C) Induced fit theory
(D) Enzyme coenzyme theory

Answer:Induced fit theory
17 A high content of triglycerides are found in
(A) VLDL
(B) LDL
(C) HDL
(D) Chylomicrons

Answer: Chylomicrons
18 Haemoglobin has
(A) Primary structure
(B) Secondary structure
(C) Tertiary structure
(D) Quaternary structure

Answer:Quaternary structure
19 Which is the most abundant biomolecule on earth?
(A) Mineral salts
(B) Proteins
(C) Lipids
(D) Carbohydrates

Answer: Carbohydrates
20 In which of the following an anticodon occurs
(A) tRNA
(B) mRNA
(C) rRNA
(D) DNA

Answer: tRNA
21 Platelet aggregation:
(A) is initiated at the site of an injury by conversion of fibrinogen to fibrin
(B) is inhibited in uninjured blood vessels by the secretion of prostacyclin by intact vascular endothelium
(C) causes morphological changes and a release of the vasodilator serotonine
(D) is inhibited by the release of ADP and thromboxane A2

Answer:is inhibited by the release of ADP and thromboxane A2
22 The cones of the retina:
(A) are responsible for colour vision
(B) are much more numerous than rods
(C) have red, blue and green light- sensitive pigments that differ because of small difference in the retinal prosthetic group
(D) do not use transducin in signal transduction

Answer: are responsible for colour vision
23 The nerve impulse that initiates muscular contraction
(A) begins with the binding of acetyl choline to receptors in the sarcoplasmic reticulum
(B) causes both the plasma membrane and the transverse tubules to undergo hyperpolariation
(C) causes opening of calcium channels which lead to an increase in calcium contreation within the sarcomere
(D) prevents sodium entering the sarcomere

Answer: causes opening of calcium channels which lead to an increase in calcium contreation within the sarcomere
24 When a muscle contracts, the
(A) Transverse tubules shorten, the myofibrils and sarcoplasmic reticulum close together
(B) Thin filaments and thick filaments of the sarcomere shorten
(C) Light chains dissociate from the heavy chains of myosin
(D) H bands and I bands of the sarcomere shorten because the thin filaments and thick filaments side past each other

Answer:H bands and I bands of the sarcomere shorten because the thin filaments and thick filaments side past each other
25 Lysis of a fibrin clot:
(A) is an equibrium wwith formation of the clot
(B) begins when plasmin binds to the clot
(C) requires the hydrolysis of plasminogen into heavy and light chains
(D) requires conversion of plasminogen by tissue plasminogen activator

Answer: requires conversion of plasminogen by tissue plasminogen activator
26 ATP concentration is maintained relatively constant during muscle contraction by
(A) increasing the metabolic activity
(B) the action of adenylate kinase
(C) theaction of creatne phosphokinase
(D) all of the above

Answer: all of the above
27 4-hydroxy proline is present in
(A) Collagen
(B) Plant cell wall
(C) Keratin
(D) Both plant cell wall and collagen

Answer: Both plant cell wall and collagen
28 Peptide bonds between amino acids are highly stable and have a half-life of seven years in intracellular condition. This is due to
(A) High activation energy required for hydrolysis
(B) Low activation energy required for hydrolysis
(C) Peptide bond is a covalent bond
(D) Peptide bond is rigid and planar

Answer:High activation energy required for hydrolysis
29 Tri-peptide consists
(A) 3 amino acids and 3 peptide bonds
(B) 2 amino acids and 3 peptide bonds
(C) 3 amino acids and 2 peptide bonds
(D) 3 amino acids and 4 peptide bonds

Answer:3 amino acids and 2 peptide bonds
30 All the following statements are true except
(A) Ornithine and citrulline are uncommon aminoacids
(B) Ornithine is an intermediates in Urea cycle
(C) Ormithine and citrulline are uncommon amino acids present in many proteins
(D) Both ornithine and citrulline are intermediates in urea cycle

Answer: Ormithine and citrulline are uncommon amino acids present in many proteins
31 PDI is an enzyme involve in
(A) Protein synthesis
(B) Protein degradation
(C) Protein folding
(D) Protein quaternery structure formation

Answer:Protein folding
32 The most abundant biomolecule on earth
(A) proteins
(B) lipids
(C) nucleic acids
(D) carbohydrates

Answer: carbohydrates
33 Carbohydrates are
(A) polyhydroxy alkynes or aldehydes
(B) polyhydroxy phenols or aldehydes
(C) polyhydroxy ketones or aldehydes
(D) polyhydroxy alkenes and aldehydes

Answer:polyhydroxy ketones or aldehydes
34 Carbohydrates occur naturally in
(A) L- form and D-form
(B) L- form only
(C) D- form only
(D) Dependent on the pH

Answer:D- form only
35 The width of DNA molecule is
(A) 15 Ao
(B) 3.4 Ao
(C) 20 Ao
(D) 25 Ao

Answer: 20 Ao
36 The most important interaction that contribute to polysaccharide folding
(A) Ionic bond
(B) hydrophobic interaction
(C) Vanderwalls interaction
(D) hydrogen bond

Answer: hydrogen bond
37 All of the following are extracellular heteropolyscacharides except
(A) dextran
(B) chondroitin
(C) hyaluronate
(D) dermatan sulpahte

Answer: dextran
38 Functions of carbohydrates include
(A) cell recognition
(B) cell to cell interaction
(C) imparting structure and store energy
(D) All of the above

Answer:All of the above
39 Lipopolysaccharide in the outer membrane is responsible for the antigenic property in
(A) Gram positive bacteria
(B) Gram positive and gram negative bacteria
(C) Gram negative bacteria
(D) Actinomycetes

Answer: Gram negative bacteria
40 Many plasma glycoproteins has a terminal sialic acid residue that helps in
(A) cell to cell recognition
(B) cells interaction with extracellular matrix
(C) protection form degradation by liver
(D) generating signals that favours degradation by liver

Answer: protection form degradation by liver
41 The backbone of DNA is
(A) hydrophilic
(B) hydrophobic
(C) nuetral
(D) Both hydrophilic and hydrophobic

Answer:hydrophilic
42 Which is the most stable form of DNA under normal physiological conditions
(A) A-DNA
(B) B-DNA
(C) Z-DNA
(D) H-DNA

Answer: B-DNA
43 As far as the absorbance of DNA at 260nm. Which of the following is correct?
(A) individual nucleotides>ss DNA>dsDNA
(B) dsDNA>ssDNA> individual nucleotides
(C) ssDNA>dsDNA> individual nucleotides
(D) absorbance remains same

Answer:individual nucleotides>ss DNA>dsDNA
44 Which of the following statement is true?
(A) DNA is more stable than RNA in alkaline condition because of the presence of 3’OH
(B) DNA is more stable than RNA in alkaline condition because of the presence of 2’ H compared to RNAs 2’OH
(C) RNA is more stable than DNA in alkaline condition because of the presence of 2’ and 3’OH compared to DNAs 2’H and 3’OH
(D) Both are equally stable in alkaline condition

Answer:DNA is more stable than RNA in alkaline condition because of the presence of 2’ H compared to RNAs 2’OH
45 Dehydration of DNA samples may induce the formation of
(A) A-DNA
(B) B-DNA
(C) Z-DNA
(D) H-DNA

Answer: A-DNA
46 An increase in temperature of a DNA sample causes change in
(A) absorbance at 260nm
(B) viscosity
(C) phosphodiester linkage
(D) absorbance and viscosity

Answer:absorbance and viscosity
47 RNA-DNA hybrids are
(A) more stable than DNA-DNA hybrid
(B) more stable than RNA-RNA hybrid
(C) less stable than RNA-RNA hybrid
(D) less stable than RNA-RNA hybrid and DNA-DNA hybrid

Answer: less stable than RNA-RNA hybrid and DNA-DNA hybrid
48 An increase Tm (melting temperature) for a ds-DNA may be due to high content of
(A) A+G
(B) A+T
(C) C+G
(D) none of the above

Answer:C+G
49 Thymine is present in
(A) prokaryotic mRNA
(B) mammalian mRNA
(C) ribosomal RNA
(D) tRNA

Answer:tRNA
50 RNA is genetic material in
(A) some virusus and prokaryotes
(B) some viruses only
(C) some virusus, prokaryotes and some primitive eukaryotes
(D) none of the above

Answer:some virusus and prokaryotes
51 Lectins are
(A) Carbohydrate degrading proteins
(B) proteins that binds to carbohydrates with high affinity and specificity
(C) are glycoproteins that binds to carbohydrates
(D) are glycoproteins present in bacteria

Answer: proteins that binds to carbohydrates with high affinity and specificity
52 Selectins are
(A) Plasma membrane lectins involved in cell-cell recognition
(B) cytosolic lectins involved in intracellular signalling
(C) Plasma membrane glycoproteins involved in cell to cell interaction
(D) Plasma membrane glycoproteins that functions as second messengers

Answer: Plasma membrane lectins involved in cell-cell recognition
53 Lectins binds preferentially to
(A) more polar region of the carbohydrate residue
(B) less polar region of the carbohydrate residue
(C) both polar and non-polar region of the carbohydrate residue
(D) All of the above

Answer: more polar region of the carbohydrate residue
54 Glycosylation takes place in
(A) SER and golgi
(B) RER and golgi
(C) SER, RER and golgi
(D) RER, golgi and mitochondria

Answer: RER and golgi
55 O- linked oligosaccharides are attached to the protein via
(A) OH group of serine or tyrosine
(B) OH group of serine or threonine
(C) OH group of tyrosine or threonine
(D) OH group of threonine only

Answer: OH group of serine or threonine
56 N-linked oligosaccharides are linked to protein via NH2 groups of Asparagine. The sequence containing asparagine is usually asp-X-ser/thr. X can be any amino acid except
(A) glycine
(B) histidine
(C) proline
(D) serine

Answer:proline
57 The pentoses in nucleotides are
(A) in β-furanose form
(B) in α-furanose form
(C) Both
(D) none of the above

Answer: in β-furanose form
58 To identify self DNA from non-self DNA, the self DNA may be
(A) glycosylated
(B) carboxylated
(C) phosphorylated
(D) methylated

Answer:methylated
59 The length of DNA having 23 base pairs is
(A) 78 Ao
(B) 78.4 Ao
(C) 78.2 Ao
(D) 74.8 Ao

Answer:74.8 Ao
60 Choose the best option
(A) proteins has catalytic activity
(B) Proteins and RNA have catalytic activity
(C) Proteins, RNA and antibodies have catalytic activity
(D) Proteins, RNA, antibodies and phospholipids have catalytic activity

Answer: Proteins, RNA and antibodies have catalytic activity
61 The characteristic strong absorbance of 280nm of proteins is due to
(A) All amino acids can absorb at 280nm
(B) Only Tryptophan and tyrosine can absorb at 280 nm
(C) Tryptophan is responsible for the absorbance
(D) Tryptophan, tyrosine and phenylalanine can absorb at 280 nm

Answer: Tryptophan, tyrosine and phenylalanine can absorb at 280 nm
62 The formation of cystine occurs at
(A) ER
(B) Golgi
(C) Cytosol
(D) Mitochondria

Answer: ER
63 A short length of DNA molecule has 80 thymine and 80 guanine bases. The total number of nucleotide in the DNA fragment is
(A) 160
(B) 40
(C) 320
(D) 640

Answer: 320
64 Which of the following aminoacid has pKa near neutrality
(A) Tryptophan
(B) Arginine
(C) Histidine
(D) Asparagine

Answer: Histidine
65 Desmosine is an unusual amino acid found in
(A) Myosin
(B) Troponin
(C) Actin
(D) Elastin

Answer: Elastin
66 How many small peptides are formed upon cleavage by trypsin if a protein has 5 lysine residues
(A) 4
(B) 5
(C) 6
(D) 7

Answer:6
67 EF-1α and EF-Tu are
(A) Analogs
(B) Homologs
(C) Paralogs
(D) Syllogs

Answer:Homologs
68 All the statements regarding peptide bond are true except
(A) Peptide bond is a co-valent bond
(B) Peptide bond is rigid and planar
(C) Peptide bond has partial double bond character
(D) Peptide bond is formed by non-condensation reaction

Answer:Peptide bond is formed by non-condensation reaction
69 Αlpha-helix has
(A) 3.6 residues/turn and is a right handed helix
(B) 3.8 residues/turn and is a right handed helix
(C) 3.6 residues/turn and is a left handed helix
(D) 3.8 residues/turn and is a left handed helix

Answer: 3.6 residues/turn and is a right handed helix
70 Which of the following amino acids are rarely present in alpha helix
(A) Glycine and proline
(B) Proline and tryptophan
(C) Tryptophan and glycine
(D) Proline only

Answer: Glycine and proline
71 The fastest enzyme is
(A) DNA gyrase
(B) Pepsin
(C) DNA polymerase
(D) Carbonic anhydrase

Answer: Carbonic anhydrase
72 Which of the following is a phospholipid?
(A) Sterol
(B) Cholesterol
(C) Lecithin
(D) Steroid

Answer: Lecithin
73 In double helix of DNA, the two strands are
(A) coiled around a common axis
(B) coiled differently
(C) coiled over protein sheath
(D) coiled around each other

Answer: coiled around a common axis
74 Nucleotides are building blocks of nucleic acids. Each nucleotide is a composite molecule formed by
(A) base- sugar- phosphate
(B) base- sugar- OH
(C) sugar-phosphate
(D) (base sugar phosphate)n

Answer: base- sugar- phosphate
75 The major role of minor elements inside living organisms is to act as
(A) Co factors of enzymes
(B) Binder of cell structure
(C) Constituent of hormones
(D) Building blocks of important amino acids

Answer:Co factors of enzymes
76 Lipids are insoluble in water because lipid molecules are
(A) Hydrophilic
(B) Neutral
(C) Zwitter ions
(D) Hydrophobic

Answer: Hydrophobic
77 ATP is
(A) vitamin
(B) Enzyme
(C) Nucleic acid
(D) Nucleotide

Answer: Nucleotide
78 Which of the following have carbohydrate as prosthetic group
(A) Glycoprotein
(B) Lipoprotein
(C) Nucleoprotein
(D) Chromoprotein

Answer: Glycoprotein
77 RNA is the genetic material in
(A) Viruses only
(B) In some viruses and some prokaryotes
(C) In some viruses and some prokaryotes and rarely in eukaryotes
(D) Only in some viruses

Answer: Only in some viruses
80 In which of the following groups are all polysaccharides?
(A) Sucrose, glucose and fructose
(B) Maltose, lactose and fructose
(C) glycogen, sucrose and maltose
(D) Glycogen, cellulose and starch

Answer: Glycogen, cellulose and starch
81 Amino acids are produced from
(A) Proteins
(B) Fatty acids
(C) Essential oils
(D) α-keto acids

Answer:Proteins
82 In RNA, thymine is replaced by
(A) adenine
(B) guanine
(C) cytosine
(D) uracil

Answer: uracil
83 Which purine base is found in RNA?
(A) Thymine
(B) Uracil
(C) Cytosine
(D) Guanine

Answer: Guanine
84 Which of the following nucleotide sequences contains four pyrimidine bases?
(A) GATCAATGC
(B) UAGCGGUAA
(C) GCUAGACAA
(D) both b and c

Answer: GATCAATGC
85 The sugar in RNA is
(A) Deoxyribose
(B) Ribose
(C) Hexose
(D) Fructose

Answer:Ribose
86 Enzymes, vitamins and hormones can be classified into a single category of biological chemicals, because all of these
(A) Enhance oxidative metabolism
(B) Help in regulating metabolism
(C) are conjugated proteins
(D) are exclusively synthesised in the body of a living organism as at present

Answer: Help in regulating metabolism
87 Number of essential elements in animals are
(A) 16
(B) 18
(C) 20
(D) 25

Answer: 25
88 Cellular micromoleules are
(A) amino acids, water, minerals, nucleotides and sugar
(B) glycogen, amino acids, minerals and nucleotides
(C) water, minerals, proteins and nucleotides
(D) sugars, water, mineral, nucleotides an d proteins

Answer:amino acids, water, minerals, nucleotides and sugar
89 The ratio between hydrogen and oxygen in a carbohydrate is
(A) 5:1
(B) 4:3
(C) 3:1
(D) 2:1

Answer: 2:1
90 Which one is fat soluble vitamin?
(A) vit A
(B) vit D
(C) vit E
(D) All of these

Answer:All of these
91 Thymine in DNA is replaced by
(A) Guanine in RNA
(B) Adenine in RNA
(C) Cytosine in RNA
(D) Uracil in RNA

Answer:Uracil in RNA
92 The most abundant type of RNA in the cell is
(A) rRNA
(B) mRNA
(C) tRNA
(D) hnRNA

Answer:rRNA
93 Which of the following RNA serves as adaptor molecule during protein synthesis
(A) rRNA
(B) mRNA
(C) tRNA
(D) hnRNA

Answer:tRNA
94 rRNA is synthesised in
(A) nucleus
(B) Cytoplasm
(C) RER
(D) Nucleolus

Answer:Nucleolus
95 cDNA is
(A) complementary to mRNA
(B) complementary to rRNA
(C) complementary to tRNA
(D) complementary to hnRNA

Answer:complementary to mRNA
96 Amino acids are attached to the
(A) acceptor arm of tRNA
(B) anti-codon arm of tRNA
(C) codon arm of tRNA
(D) none of these

Answer:acceptor arm of tRNA
97 Ribozymes are
(A) enzymes with catalytic activity
(B) RNAs with catalytic activity
(C) proteins with catalytic activity
(D) nucleic acids with catalytic activity

Answer:RNAs with catalytic activity
98 RNA is primarily seen in
(A) nucleus
(B) Cytoplasm
(C) RER
(D) SER

Answer:Cytoplasm
99 Ribose sugar in RNA is
(A) D-ribose
(B) L-ribose
(C) Both L and D form
(D) None of these

Answer:D-ribose
100 Which of the virus has double stranded RNA as genetic material?
(A) Tobacco mosaic virus
(B) Influenza virus
(C) Rous Sarcoma virus
(D) Reoviruses

Answer:Reoviruses

Here we published Top 100 most important Questions and Answers on Biomolecules. These are previous years questions which are asked in various exams live NEET, AIIMS, JIPMER and Board exams. These Solved Questions and Answers on Biomolecules are the best for all competitive medical exams.

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