Description : A protein reacts with biuret reagent which indicates 2 or more (A) Blood clotting (B) Peptide bond (C) Disulphide bonds (D) Hydrophobic bonds
Last Answer : Answer : B
Description : The bond in proteins that is not broken under usual conditions of denaturation: (A) Hydrophobic bond (B) Hydrogen bond (C) Disulphide bond (D) Peptide bonds
Last Answer : Answer : D
Description : The bond in proteins that is not hydrolysed under usual conditions of denaturation: (A) Hydrophobic bond (B) Hydrogen bond (C) Disulphide bond (D) Peptide bonds
Last Answer : Answer : C
Description : Bonds that are formed between two cysteine residues is (A) Disulphide (B) Peptide (C) Electrostatic (D) Hydrophobic
Last Answer : Answer : A
Description : α-Helix is formed by (A) Hydrogen bonds (B) Hydrophobic bonds (C) Electrostatic bonds (D) Disulphide bonds
Description : Primary structure of a protein is formed by (A) Hydrogen bonds (B) Peptide bonds (C) Disulphide bonds (D) All of these
Description : At the lowest energy level α-helix of polypeptide chain is stabilised (A) By hydrogen bonds formed between the H of peptide N and the carbonyl O of the residue (B) Disulphide bonds (C) Non polar bonds (D) Ester bonds
Description : Which bonds are the last to break when an enzyme is heated 1 disulphide 2 hydrogen 3 hydrophobic interactions 4 ionic?
Last Answer : ionic
Description : In denaturation of proteins, the bond which is not broken: (A) Disulphide bond (B) Peptide bond (C) Hydrogen bond (D) Ionic bond
Description : The two strands of the DNA double helix are held together by (a) Hydrogen bonds (b)C=C double bonds (c) Hydrophobic bonds (d) Peptide bonds
Last Answer : Ans:(a)
Description : Many globular proteins are stable in solution although they lack in (A) Hydrogen bonds (B) Salt bonds (C) Non-polar bonds (D) Disulphide bonds
Description : The a-helix of proteins is (A) A pleated structure (B) Made periodic by disulphide bridges (C) A non-periodic structure (D) Stabilised by hydrogen bonds between NH and CO groups of the main chain
Description : Many globular proteins are stable in solution inspite they lack in (A) Disulphide bonds (B) Hydrogen bonds (C) Salt bonds (D) Non polar bonds
Description : In quaternary structure, subunits are linked by (A) Peptide bonds (B) Disulphide bonds (C) Covalent bonds (D) Non-covalent bonds
Description : Denaturation of proteins results in (A) Disruption of primary structure (B) Breakdown of peptide bonds (C) Destruction of hydrogen bonds (D) Irreversible changes in the molecule
Description : Which of the following is the least likely to be involved in stabilising the three-dimensional folding of most proteins (a) Hydrogen bonds (b) Electrostatic interaction (c) Hydrophobic interaction (d) Ester bonds
Last Answer : (d) Ester bonds
Description : Tertiary structure of a protein describes (A) The order of amino acids (B) Location of disulphide bonds (C) Loop regions of proteins (D) The ways of protein folding
Description : α-helix is stabilized by (A) Hydrogen bonds (B) Disulphide bonds (C) Salt bonds (D) Non-polar bonds
Description : Indole group of tryptophan responses positively to (A) Glyoxylic acid (B) Schiff’s reagent (C) Biuret test (D) Resorcinol test
Description : The useful reagent for detection of amino acids is (A) Molisch reagent (B) Dichlorophenol Indophenol (C) Ninhydrin (D) Biuret
Description : Biuret test is specific for (A) Two peptide linkage (B) Phenolic group (C) Imidazole ring (D) None of these
Description : Group that reacts in the Biuret test: (A) Peptide (B) Amino group (C) Carboxylic group (D) Aldehyde group
Description : A coiled structure in which peptide bonds are folded in regular manner by (A) Globular proteins (B) Fibrous proteins (C) Both (A) and (B) (D) None of these
Description : All the following statements about pepsin are correct except (A) It is smaller than pepsinogen (B) It is formed by the action of HCl on its precursor (C) Its optimum pH is 1.0–2.0 (D) It hydrolyses the C-terminal and N-terminal peptide bonds of proteins
Description : The chemical forces that bind most coenzymes and substrates to enzymes such as LDH are (A) Hydrogen bonds (B) Peptide bonds (C) Coordinate bonds (D) Covalent bonds
Description : The hydrogen bonds between peptide linkages are interfered by (A) Guanidine (B) Uric acid (C) Salicylic acid (D) Oxalic acid
Description : The hydrogen bonds between peptide linkages of a protein molecules are interfered by (A) Guanidine (B) Uric acid (C) Oxalic acid (D) Salicylic acid
Description : The two polypeptides of human insulin are linked together by (a) covalent bond (b) disulphide bridges (c) hydrogen bonds (d) phosphodiester bond.
Last Answer : (b) disulphide bridges
Description : What are the Reaction of amino acid using ninhydrin and biuret reagent?
Last Answer : What is the answer ?
Description : Peptide bonds are found in: a) carbohydrates b) lipids c) nucleic acids d) proteins
Last Answer : ANSWER: D -- PROTEINS
Description : The number of intra-chain disulphide bonds in pro-insulin: (A) One (B) Two (C) Three (D) Four
Description : Hydrophobic bonds are formed in protein be- tween which amino acids?
Last Answer : Valine, leucine and isoleucine residues.
Description : Which of the following statements is not correct? (a) In man insulin is synthesised as a proinsulin. (b) The proinsulin has an extra peptide called C-peptide. (c) The functional insulin has A and B chains linked together by hydrogen bonds. (d) Genetically engineered insulin is produced in E.Coli.
Last Answer : (c) The functional insulin has A and B chains linked together by hydrogen bonds.
Description : The double helical structure of DNA is held together by (a) sulfur-sulfur linkages (b) peptide bonding (c) hydrogen bonding (d) glycosidic bonds
Last Answer : hydrogen bonding
Description : Folding of newly synthesized proteins is accelerated by (A) Protein disulphide isomerase (B) Prolyl cis-trans isomerase (C) Chaperonins (D) All of these
Description : The hydrogen bonds in the secondary and tertiary structure of proteins are directly attacked by (A) Salts (B) Alkalies (C) Detergents (D) All of these
Description : The structural stability of the double helix of DNA is as cribbed largely to (A) Hydrogen bonding between adjacent purine bases (B) Hydrophobic bonding between staked purine and ... Hydrogen bonding between adjacent pyrimidine bases (E) Hydrogen bonding between purine and pyrimidine bases
Description : The formation of a peptide bond during the elongation step of protein synthesis results in the splitting of how many high energy bonds? (A) 1 (B) 2 (C) 3 (D) 4
Description : Ninhydrin reaction gives a purple colour and evolves CO2 with (A) Peptide bonds (B) Histamine (C) Ergothioneine (D) Aspargine
Description : The only correct statement about chymotrypsin is (A) It is formed from trypsin (B) Carboxypeptidase converts trypsin into chymotrypsin (C) Its optimum pH is around 7 (D) It hydrolyses peptide bonds involving basic amino acids
Description : Edman’s reaction can be used to (A) Determine the number of tyrosine residues in a protein (B) Determine the number of aromatic amino acid residues in a protein (C) Determine the amino acid sequence of a protein (D) Hydrolyse the peptide bonds in a protein
Description : Chymotrypsin is specific for peptide bonds containing (A) Uncharged amino acid residues (B) Acidic amino acids (C) Basic amino acid (D) Small amino acid residues
Description : The enzyme trypsin is specific for peptide bonds of (A) Basic amino acids (B) Acidic amino acids (C) Aromatic amino acids (D) Next to small amino acid residues
Description : How many peptide bonds are present in a trip- eptide?
Last Answer : A tripeptide is a combination of three amino ac- ids; so there are two peptide bonds.
Description : Primary structure of proteins can be determined by the use of (A) Electrophoresis (B) Chromatography (C) Ninhydrin (D) Sanger’s reagent
Description : What does biuret solution specifically react with to produce a color change?
Last Answer : amino acids
Description : Which of the following tests is not used for testing proteins? (a) Ninhydrin test (b) Biuret test (c) Xanthoproteic test (d) Tollens' test
Last Answer : Tollens' test
Description : Which of the following statement(s) is/are true concerning the cell plasma membrane? a. The plasma membrane is composed of amphipathic molecules b. The hydrophobic core of the lipid bilayer of the ... contribute to the cell coat d. The membrane proteins of nerve cells are highly voltage-dependent
Last Answer : Answer: a, b, d The plasma membrane defines the boundary of the cell and serves to contain and concentrate enzymes and other macromolecule constituents. The plasma membrane is ... and bear carbohydrate moieties primarily as oligosaccharide chains that contribute to the cell coat or glycocalyx
Description : In fluid mosaic model of plasma membrane (a) upper layer is non-polar and hydrophilic (b) upper layer is polar and hydrophobic (c) phospholipids form a bimolecular layer in middle part (d) proteins form a middle layer.
Last Answer : (c) phospholipids form a bimolecular layer in middle part