12th Class Chemistry Biomolecules / जैव-अणु Question Bank

done MCQs - Biomolecules Total Questions - 60

• question_answer1)
  Which of the following is an example of an aldopentose?
  A)
  D-Ribose done clear
  B)
  Glyceraldehyde done clear
  C)
  Fructose done clear
  D)
  Erythrose done clear
  View Solution play_arrow

• question_answer2)
  Which of the following pair represent anomers?
  A)
  done clear
  B)
  done clear
  C)
  done clear
  D)
  done clear
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• question_answer3)
  Match the sugars in column I with their types given in column II and mark the appropriate choice.

  	Column - I		Column - II
  [A]	Glucose	(i)	Ketohexose
  [B]	Fructose	(ii)	Aldohexose
  [C]	Ribose	(iii)	Aldotetrose
  [D]	Erythrose	(iv)	Aldopentose

  A)
  [A] \[\to \] (iv), [B] \[\to \] (i), [C] \[\to \] (iii), [D] \[\to \] (ii) done clear
  B)
  [A] \[\to \] (iii), [B] \[\to \] (iv), [C] \[\to \] (i), [D] \[\to \] (ii) done clear
  C)
  [A] \[\to \] (i), [B] \[\to \](ii), [C] \[\to \] (iii), [D] \[\to \] (iv) done clear
  D)
  [A] \[\to \] (ii), [B] \[\to \] (i), [C] \[\to \] (iv), [D]\[\to \] (iii) done clear
  View Solution play_arrow

• question_answer4)
  Amino acids generally exist in the form of Zwitter ions. This means they contain
  A)
  basic \[-N{{H}_{2}}\] group and acidic —COOH group done clear
  B)
  the basic \[-\overset{+}{\mathop{N}}\,{{H}_{3}}\] group and acidic \[CO{{O}^{-}}\] group done clear
  C)
  basic \[N{{H}_{2}}\] and acidic \[{{H}^{+}}\] group done clear
  D)
  basic —\[CO{{O}^{-}}\] group and acidic \[-\overset{+}{\mathop{N}}\,{{H}_{3}}\] group. done clear
  View Solution play_arrow

• question_answer5)
  During acetylation of glucose it needs x moles of acetic anhydride. The value of x would be
  A)
  3 done clear
  B)
  5 done clear
  C)
  4 done clear
  D)
  1 done clear
  View Solution play_arrow

• question_answer6)
  Which compound can exist in a dipolar (zwitter ion) structure?
  A)
  \[{{C}_{6}}{{H}_{5}}C{{H}_{2}}CH\left( N=C{{H}_{2}} \right)COOH\] done clear
  B)
  \[{{\left(C{{H}_{3}} \right)}_{2}}CHCH\left( N{{H}_{2}} \right)COOH\] done clear
  C)
  \[{{C}_{6}}{{H}_{5}}CONHC{{H}_{2}}COOH\] done clear
  D)
  \[HOOCC{{H}_{2}}C{{H}_{2}}COCOOH\] done clear
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• question_answer7)

  The given structures (I) and (II) represent configuration of the simplest sugar glycer-aldehyde. Which of the following statements is not correct for the structures?

  \[\underset{\left( I \right)}{\mathop{H-\underset{\begin{smallmatrix} |\\ CH{{ }_{2}}OH \end{smallmatrix}}{\overset{\begin{smallmatrix} CHO\\ | \end{smallmatrix}}{\mathop{C}}}\,-OH}}\,\,\,\,\,\underset{\left( II \right)}{\mathop{HO-\underset{\begin{smallmatrix} |\\ CH{{ }_{2}}OH \end{smallmatrix}}{\overset{\begin{smallmatrix} CHO\\ | \end{smallmatrix}}{\mathop{C}}}\,-H}}\,\]

   
  A)
  (I) represents D-form while (II) represents L-form of glyceraldehyde. done clear
  B)
  The sugars having same configuration as D-glyceraldehyde are designated as D-sugars. done clear
  C)
  Natural glucose and fructose are D-forms. done clear
  D)
  D is dextrorotatory while L is laevorotatory enantiomer. done clear
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• question_answer8)
  Globular proteins are present in
  A)
  blood done clear
  B)
  eggs done clear
  C)
  milk done clear
  D)
  all of these done clear
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• question_answer9)
  The anomeric carbon in D(+) glucose is 
  A)
  C-1 carbon done clear
  B)
  C-2 carbon  done clear
  C)
  C-5 carbon done clear
  D)
  C-6 carbon done clear
  View Solution play_arrow

• question_answer10)
  In fibrous proteins, polypeptide chains are held together by
  A)
  van der waals forces done clear
  B)
  eletrostatic forces of attraction done clear
  C)
  hydrogen bonds done clear
  D)
  covalent bonds. done clear
  View Solution play_arrow

• question_answer11)

  Study the structures of \[\alpha \]-D - (+) glucopyranose and \[\beta \]- D(+) glucopyranose and mark the correct

  A)
  Structures I and II are enantiomers. done clear
  B)
  Structures I and II are anomers. done clear
  C)
  The two structures I and II differ in the configuration of \[{{C}_{1}}\] and \[{{C}_{4}}\]. done clear
  D)
  Both the structures I and II give 2, 4-DNP test. done clear
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• question_answer12)
  Match the column I with column II and mark the appropriate choice.

  	Column I		Column II
  [A]	Nucleoside	(i)	Sugar + base + phosphoric acid group
  [B]	Nucleotide	(ii)	Cytosine + uracil
  [C]	DNA	(iii)	Sugar + base
  [D]	RNA	(iv)	Cytosine + thymine

  A)
  [A] \[\to \] (iii), [B] \[\to \] (i), [C] \[\to \] (iv), [D] \[\to \] (ii) done clear
  B)
  [A] \[\to \] (i), [B] \[\to \] (iv), [C] \[\to \] (iii), [D] \[\to \] (ii) done clear
  C)
  [A] \[\to \] (ii), [B] \[\to \] (iii), [C] \[\to \] (i), [D] \[\to \] (iv) done clear
  D)
  [A] \[\to \] (iv), [B] \[\to \] (ii), [C] \[\to \] (i), [D] \[\to \] (iii) done clear
  View Solution play_arrow

• question_answer13)
  A unit in nucleic acid which contains 'base- sugar phosphate' unit is called
  A)
  nucleotide done clear
  B)
  nucleoside done clear
  C)
  phosphotide done clear
  D)
  polypeptide. done clear
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• question_answer14)
  The general formula of carbohydrates is
  A)
  \[{{C}_{n}}{{H}_{2n+1}}O\] done clear
  B)
  \[{{C}_{n}}{{H}_{2n}}O\] done clear
  C)
  \[{{C}_{x}}{{\left( {{H}_{2}}O \right)}_{y}}\] done clear
  D)
  \[{{C}_{n}}{{\left( {{H}_{2}}O \right)}_{2n}}\] done clear
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• question_answer15)
  If one strand of DNA has the sequence ATGCTTGA, the sequence in the complimentary strand would be
  A)
  TCCGAACT done clear
  B)
  TACGTAGT done clear
  C)
  TACGAATC done clear
  D)
  TACGAACT done clear
  View Solution play_arrow

• question_answer16)
  Glucose  \[\xrightarrow{B{{r}_{2}}\,water}\] product is
  A)
  hexanoic acid done clear
  B)
  gluconic acid done clear
  C)
  saccharic acid done clear
  D)
  bromohexane. done clear
  View Solution play_arrow

• question_answer17)
  Primary structure of a protein is
  A)
  sequence in which \[\alpha \]-amino acids are linked to one another done clear
  B)
  sequence in which amino acids of one polypeptide chain are joined to other chain done clear
  C)
  the folding patterns of polypeptide chains done clear
  D)
  the pattern in which the polypeptide chains are arranged. done clear
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• question_answer18)
  When adenine is attached to ribose sugar, it is called adenosine. To make a nucleotide from it, would require
  A)
  oxygenation done clear
  B)
  addition of a base done clear
  C)
  addition of phosphate done clear
  D)
  hydrogenation. done clear
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• question_answer19)
  Which one of the amino acids can be synthesised in the body?
  A)
  Alanine done clear
  B)
  Lysine done clear
  C)
  Valine done clear
  D)
  Histidine done clear
  View Solution play_arrow

• question_answer20)

  Among the following statements about the molecules X and Y, which is incorrect ?

  A)
  X and Y are diastereomers. done clear
  B)
  X and Y are enantiomers. done clear
  C)
  X and Y are both aldohexoses. done clear
  D)
  X is a D-sugar and Y is L-sugar. done clear
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• question_answer21)
  Which of the following is not true about amino acids?
  A)
  They are constituents of all proteins. done clear
  B)
  Alanine having one amino and one carboxylic group. done clear
  C)
  Most naturally occurring amino acids have D-configuration. done clear
  D)
  Glycine is the only naturally occurring amino acid which is optically inactive. done clear
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• question_answer22)

  Five-membered ring structures of fructose are given below. Mark the incorrect statement.

  A)
  The five-membered ring structures are named as furanose structures. done clear
  B)
  The cyclic structures represent two anomers of fructose. done clear
  C)
  Five-membered ring structures are named as pyranose structures. done clear
  D)
  These are also called Haworth structures. done clear
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• question_answer23)
  Which of the following represents a peptide chain?
  A)
  \[-NH-\underset{\begin{smallmatrix} ||\\ O \end{smallmatrix}}{\mathop{C}}\,-NH-\underset{|}{\overset{|}{\mathop{C}}}\,-NH-\underset{\begin{smallmatrix} ||\\ O \end{smallmatrix}}{\mathop{C}}\,-NH-\] done clear
  B)
  \[-NH-\underset{\begin{smallmatrix} ||\\ O \end{smallmatrix}}{\mathop{C}}\,-C{{H}_{2}}-C{{H}_{2}}C{{H}_{2}}-NH-C{{H}_{2}}C{{H}_{2}}-\underset{\begin{smallmatrix} ||\\ O \end{smallmatrix}}{\mathop{C}}\,-\] done clear
  C)
  \[-NH-C{{H}_{2}}-\underset{\begin{smallmatrix} ||\\ O \end{smallmatrix}}{\mathop{C}}\,-NH-C{{H}_{2}}-\underset{\begin{smallmatrix} ||\\ O \end{smallmatrix}}{\mathop{C}}\,-NH-C{{H}_{2}}-\] done clear
  D)
  \[-NH-C{{H}_{2}}C{{H}_{2}}-\underset{\begin{smallmatrix} ||\\ O \end{smallmatrix}}{\mathop{C}}\,-NH-NH-C{{H}_{2}}-\underset{\begin{smallmatrix} ||\\ O \end{smallmatrix}}{\mathop{C}}\,-C{{H}_{2}}-\] done clear
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• question_answer24)
  Which of the following statements is not correct?
  A)
  Only \[\alpha \]-amino acids are obtained on hydrolysis of proteins. done clear
  B)
  The ammo acids which are synthesised in the body are known as non-essential amino acids. done clear
  C)
  There are 20 essential amino acids. done clear
  D)
  L-amino acids are represented by writing the \[N{{H}_{2}}\] group on the left side. done clear
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• question_answer25)
  Which of the following statements is not true?
  A)
  Glucose and fructose both are monosaccharides. done clear
  B)
  The natural glucose and fructose are D-forms. done clear
  C)
  The solution having equal molecules of D-glucose and D-fructose is termed as invert sugar. done clear
  D)
  Aldohexoses exist in \[{{2}^{6}}\]optical forms. done clear
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• question_answer26)
  The melting points of amino acids are higher than the corresponding halo-acids because
  A)
  amino acids exist as zwitter ions resulting in strong dipole - dipole attraction done clear
  B)
  amino acids are optically active done clear
  C)
  due to higher molecular mass of \[-N{{H}_{2}}\] group molecular mass of amino acids is higher done clear
  D)
  they interact with water more than halo - acids and have salt like structure. done clear
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• question_answer27)
  Which of the following is not a function of proteins?
  A)
  Formation of hair, wool, skin and nails. done clear
  B)
  As a biological catalysts in the form of enzymes. done clear
  C)
  As food in the form of meat, eggs. done clear
  D)
  As energy provider for metabolism. done clear
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• question_answer28)
  Which of the following statements is not correct?
  A)
  Proteins are polyamides formed from amino acids. done clear
  B)
  Except glycine, all other amino acids show optical activity. done clear
  C)
  Natural proteins are commonly made up of L-isomer of amino acids. done clear
  D)
  In a-amino acids, \[-N{{H}_{2}}\] and \[-COOH\] groups are attached to different carbon atoms. done clear
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• question_answer29)
  Which of the following bases is not present in RNA?
  A)
  Adenine done clear
  B)
  Guanine done clear
  C)
  Cytosine done clear
  D)
  Thymine done clear
  View Solution play_arrow

• question_answer30)
  Secondary structure of protein refers to
  A)
  sequence of amino acids in polypeptide chain done clear
  B)
  bonds between alternate polypeptide chains done clear
  C)
  folding patterns of polypeptide chain done clear
  D)
  bonding between \[NH_{3}^{+}\] and \[CO{{O}^{-}}\] of two peptides. done clear
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• question_answer31)
  In DNA, the complimentary bases are
  A)
  uracil and adenine, cytosine and guanine done clear
  B)
  adenine and thymine, guanine and cytosine done clear
  C)
  adenine and thymine, guanine and uracil done clear
  D)
  adenine and guanine, thymine and cytosine. done clear
  View Solution play_arrow

• question_answer32)
  The peptide linkage formed between glycine \[\left( N{{H}_{2}}C{{H}_{2}}COOH \right)\]and alanine (\[N{{H}_{2}}\underset{\begin{smallmatrix} |\\ C{{H}_{3}} \end{smallmatrix}}{\mathop{CH}}\,-COOH\]) to give glycylalanine can be shown as
  A)
  \[N{{H}_{2}}-C{{H}_{2}}-NH-\underset{\begin{smallmatrix} |\\ C{{H}_{3}} \end{smallmatrix}}{\mathop{CH}}\,-COOH\] done clear
  B)
  \[N{{H}_{2}}-C{{H}_{2}}-CONH-\underset{\begin{smallmatrix} |\\ C{{H}_{3}} \end{smallmatrix}}{\mathop{CH}}\,-COOH\] done clear
  C)
  \[{{H}_{2}}NCOC{{H}_{2}}-\underset{\begin{smallmatrix} |\\ C{{H}_{3}} \end{smallmatrix}}{\mathop{CH}}\,-CONH\] done clear
  D)
  \[HOOC-C{{H}_{2}}-NH-NH-\underset{\begin{smallmatrix} |\\ C{{H}_{3}} \end{smallmatrix}}{\mathop{CH}}\,-COOH\] done clear
  View Solution play_arrow

• question_answer33)
  Number of stereocentres present in linear and cyclic structures of glucose are respectively.
  A)
  4 and 4 done clear
  B)
  4 and 5 done clear
  C)
  5 and 5 done clear
  D)
  5 and 4 done clear
  View Solution play_arrow

• question_answer34)
  Which type of interactions are responsible for making the a-helix structure stable?
  A)
  Peptide bonds between \[-N{{H}_{2}}\] and \[CO\] groups of adjacent carbon chains. done clear
  B)
  Hydrogen bonds between —NH of amino acid in one turn with —CO of amino acid to adjacent turn. done clear
  C)
  —OH group of one amino acid with —CO group of other amino acid on the turn. done clear
  D)
  Hydrogen bonds between adjacent amino acids. done clear
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• question_answer35)
  Proteins are condensation polymers of
  A)
  \[\alpha \]-amino acids done clear
  B)
  \[\beta \]-amino acids done clear
  C)
  \[\alpha \]-hydroxy acids done clear
  D)
  \[\beta \]-hydroxy acids. done clear
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• question_answer36)
  Which of the following reactions could not be explained on the basis of open chain structure of glucose?
  A)
  Pentaacetate of glucose does not react with \[N{{H}_{2}}OH\]. done clear
  B)
  Glucose on prolonged heating with HI gives n-hexane. done clear
  C)
  Glucose on oxidation with bromine water forms gluconic acid. done clear
  D)
  With acetic anhydride glucose gives pentaacetate. done clear
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• question_answer37)
  Denaturation of protein leads to loss of its biological activity by
  A)
  formation of amino acids done clear
  B)
  loss of primary structure done clear
  C)
  loss of both primary and secondary structure done clear
  D)
  loss of both secondary and tertiary structure. done clear
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• question_answer38)
  Which of the following is an acidic amino acid?
  A)
  Glycine done clear
  B)
  Valine done clear
  C)
  Leucine done clear
  D)
  Glutamic acid done clear
  View Solution play_arrow

• question_answer39)
  Bases common to RNA and DNA are
  A)
  adenine, guanine, cytosine done clear
  B)
  adenine, uracil, cytosine done clear
  C)
  adenine, guanine, thymine done clear
  D)
  guanine, uracil, thymine. done clear
  View Solution play_arrow

• question_answer40)
  How many C-atoms are involve in a pyranose ring?
  A)
  3 done clear
  B)
  5 done clear
  C)
  6 done clear
  D)
  7 done clear
  View Solution play_arrow

• question_answer41)
  Phosphodiester linkage is present between which carbon atoms of pentose sugars of nucleotides?
  A)
  5' and 3' done clear
  B)
  1' and 5' done clear
  C)
  5' and 5' done clear
  D)
  3' and 3' done clear
  View Solution play_arrow

• question_answer42)
  On boiling the egg, what structural changes are taking place in the egg white?
  A)
  The colour of the egg changes from colourless to white. done clear
  B)
  \[2{}^\circ \]and \[3{}^\circ \] structures are destroyed but \[1{}^\circ \] structure remains intact. done clear
  C)
  \[1{}^\circ \], \[2{}^\circ \] and \[3{}^\circ \]structures of egg are destroyed. done clear
  D)
  A reversible change takes place which can be reversed by decreasing the temperature. done clear
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• question_answer43)
  The letter 'D' in carbohydrates signifies
  A)
  dextrorotatory done clear
  B)
  configuration done clear
  C)
  diamagnetic nature done clear
  D)
  mode of synthesis. done clear
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• question_answer44)
  The number of amino acids found in proteins that a human body can synthesise is
  A)
  20 done clear
  B)
  25 done clear
  C)
  10 done clear
  D)
  100 done clear
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• question_answer45)
  A nucleoside on hydrolysis gives
  A)
  an aldopentose and a nitrogenous base done clear
  B)
  an aldopentose and phosphoric acid done clear
  C)
  an aldopentose, a nitrogenous base and phosphoric acid done clear
  D)
  a nitrogenous base and phosphoric acid. done clear
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• question_answer46)
  Keratin, a structural protein is present in
  A)
  hair done clear
  B)
  wool done clear
  C)
  silk done clear
  D)
  all of these. done clear
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• question_answer47)
  Glucose can be tested by following
  A)
  Tollens' reagent done clear
  B)
  Fehling's solution done clear
  C)
  both of these done clear
  D)
  none of these. done clear
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• question_answer48)
  In \[\beta \]-sheet of proteins, conformers are held together by
  A)
  intermolecular hydrogen bond done clear
  B)
  intramolecular hydrogen bond done clear
  C)
  coordinate bond done clear
  D)
  none of these. done clear
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• question_answer49)
  In an amino acid, the carboxyl group ionizes at \[p{{K}_{{{a}_{1}}}}=2\centerdot 34\] and ammonium ion at \[p{{K}_{{{a}_{2}}}}=9\centerdot 60\]. The isoelectric point of the amino is
  A)
  \[5\centerdot 97\] done clear
  B)
  \[2\centerdot 34\] done clear
  C)
  \[9\centerdot 60\] done clear
  D)
  \[6\centerdot 97\] done clear
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• question_answer50)
  Which of the following reagents cannot distinguish between glucose and fructose?
  A)
  Tollens' reagent done clear
  B)
  Fehling's solution done clear
  C)
  Benedict's solution done clear
  D)
  All of these done clear
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• question_answer51)

  Which set of terms correctly identifies the carbohydrate shown?

  1. Pentose 2. Hexose 3. Aldose 4. Ketose 5. Pyranose 6. Furanose

  A)
  1, 3 and 6 done clear
  B)
  1, 3 and 5 done clear
  C)
  2, 3 and 5 done clear
  D)
  2, 3 and 6 done clear
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• question_answer52)
  Match the column I with column II and choose the correct option.

  	Column - I		Column - II
  [A]	Lysine active amino acid	(p)	Neutral optically
  [B]	Aspartic acid	(q)	Basic amino acid
  [C]	Valine	(r)	Neutral optically inactive amino acid
  [D]	Glycine	(s)	Acidic amino acid

  A)
  A-s ; B-r ; C-q ; D-p done clear
  B)
  A-r ; B-q ; C-r ; D-p done clear
  C)
  A-p ; B-q : C-r ; D-s done clear
  D)
  A-q ; B-s ; C-p : D-r done clear
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• question_answer53)
  During the process of digestion, the proteins present in food materials are hydrolysed to amino acids. The two enzymes involved in the process are \[proteins\xrightarrow{enzyme(A)}polypeptides\xrightarrow[a\operatorname{mino}\,acids]{enzyme(B)}\]
  A)
  invertase and zymase done clear
  B)
  amylase and maltase done clear
  C)
  diastase and lipase done clear
  D)
  pepsin and trypsin. done clear
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• question_answer54)
  Which of the following statements is not correct?
  A)
  A nucleoside is an N-glycoside of heterocyclic base. done clear
  B)
  Nucleotides are phosphoesters of nucleosides. done clear
  C)
  The structure of ribose sugar is done clear
  D)
  A nucleotide has the following typical linkage \[-\overset{\begin{smallmatrix}  base\\ | \end{smallmatrix}}{\mathop{sugar}}\,-phosphate-\overset{\begin{smallmatrix}  base\\ | \end{smallmatrix}}{\mathop{sugar}}\,-phosphate-\]                      done clear
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• question_answer55)
  A tripeptide (X) on partial hydrolysis gave two dipeptides Cys-Gly and Glu-Cys. Identify the tripeptide.
  A)
  Glu-Cys-Gly done clear
  B)
  Gly-Glu-Cys done clear
  C)
  Cys-Gly-Glu done clear
  D)
  Cys-Glu-Gly done clear
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• question_answer56)
  Which of the following biomolecules simply refers to as "staff of life"?
  A)
  Lipids done clear
  B)
  Proteins done clear
  C)
  Vitamins done clear
  D)
  Carbohydrates done clear
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• question_answer57)
  The structural difference in Thymine and Uracil is —H of the Uracil is replaced by ______ in Thymine.
  A)
  \[=O\] done clear
  B)
  \[-C{{H}_{3}}\] done clear
  C)
  \[-N{{H}_{2}}\] done clear
  D)
  \[=NH\] done clear
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• question_answer58)
  The central dogma of molecular genetics states that the genetic information flows from
  A)
  Amino acids\[\to \] Proteins \[\to \] DNA done clear
  B)
  DNA \[\to \] Carbohydrates \[\to \] Proteins done clear
  C)
  DNA \[\to \] RNA \[\to \] Proteins done clear
  D)
  DNA \[\to \] RNA \[\to \] Carbohydrates done clear
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• question_answer59)

  Which   of   the   statements   about "Denaturation" given below are correct?

  (1) Denaturation of proteins causes loss of secondary and tertiary structures of the protein.

  (2) Denaturation leads to the conversion of double strand of DNA into single strand.

  (3) Denaturation affects primary structure which gets distorted.

  A)
  (2) and (3) done clear
  B)
  (1) and (3) done clear
  C)
  (1) and (2) done clear
  D)
  (1), (2) and (3) done clear
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• question_answer60)
  Which of the following groups is simplest form of a carbohydrates?
  A)
  carboxyl groups done clear
  B)
  Aldehyde and ketone groups done clear
  C)
  Alcohol and carboxyl groups done clear
  D)
  Hydroxyl groups and hydrogen groups done clear
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