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
Last Answer : Answer : A
Description : Bonds that are formed between two cysteine residues is (A) Disulphide (B) Peptide (C) Electrostatic (D) Hydrophobic
Description : α-helix is stabilized by (A) Hydrogen bonds (B) Disulphide bonds (C) Salt bonds (D) Non-polar bonds
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 : Proteins react with biuret reagent which is suggestive of 2 or more (A) Hydrogen bonds (B) Peptide bonds (C) Disulphide bonds (D) Hydrophobic bonds
Last Answer : Answer : B
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 : 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 : 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 : 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 : A protein reacts with biuret reagent which indicates 2 or more (A) Blood clotting (B) Peptide bond (C) Disulphide bonds (D) Hydrophobic bonds
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 : Primary structure of a protein is formed by (A) Hydrogen bonds (B) Peptide bonds (C) Disulphide bonds (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 : 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 : 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 many proteins the hydrogen bonding produces a regular coiled arrangement which is called as (A) β-Helix (B) α-Helix (C) Both (A) and (B) (D) Spiral
Description : In many proteins the hydrogen bonding produces a regular coiled arrangement called (A) α-helix (B) β-helix (C) Both (A) and (B) (D) None of these
Description : Hydrophobic bonds are formed in protein be- tween which amino acids?
Last Answer : Valine, leucine and isoleucine residues.
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 : Electrostatic bonds can be formed between the side chains of (A) Alanine and leucine (B) Leucine and valine (C) Asparate and glutamate (D) Lysine and aspartate
Description : The α-Helix is held in a coiled conformation partially because of : (a) Optical activity (b) Hydrogen bonding (c) Resonance (d) Delocalization
Last Answer : Hydrogen bonding
Description : The number of intra-chain disulphide bonds in pro-insulin: (A) One (B) Two (C) Three (D) Four
Description : In quaternary structure, subunits are linked by (A) Peptide bonds (B) Disulphide bonds (C) Covalent bonds (D) Non-covalent 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 : In protein structure the α-helix and βpleated sheets are example of (A) Primary structure (B) Secondary structure (C) Tertiary structure (D) Quaternary structure
Description : α-helix is disrupted by certain amino acids like (A) Proline (B) Arginine (C) Histidine (D) Lysine
Description : The distance travelled per turn of α-helix in nm is (A) 0.34 (B) 0.44 (C) 0.54 (D) 0.64
Description : Each turn of α-helix contains the number of amino acids (A) 2.8 (B) 3.2 (C) 3.4 (D) 3.6
Description : An amino acid that does not take part in α helix formation is (A) Histidine (B) Tyrosine (C) Proline (D) Tryptophan
Description : Both α-helix and β-pleated sheet conformation of proteins were proposed by (A) Watson and Crick (B) Pauling and Corey (C) Waugh and King (D) Y.S.Rao
Description : In proteins the α-helix and β-pleated sheet are examples of (A) Primary structure (B) Secondary structure (C) Tertiary structure (D) Quaternary structure
Description : Along the α-helix each amino acid residue advances in nm by (A) 0.15 (B) 0.10 (C) 0.12 (D) 0.20
Description : Each turn of α-helix contains the amino acid residues (number): (A) 3.6 (B) 3.0 (C) 4.2 (D) 4.5
Description : In denaturation of proteins, the bond which is not broken: (A) Disulphide bond (B) Peptide bond (C) Hydrogen bond (D) Ionic bond
Description : A disulphide bond can be formed between (A) Two methionine residues (B) Two cysteine residues (C) A methionine and a cysteine residue (D) All of these
Description : In DNA, three hydrogen bonds are formed between (A) Adenine and guanine (B) Adenine and thymine (C) Guanine and cytosine (D) Thymine and cytosine
Description : The α-Helix is a common form of (a) Primary structure (b) Tertiary structure (c) Secondary structure (d) None of these
Last Answer : Secondary structure
Description : The primary structure of a protein refers to : (a) whether the protein is fibrous or globular (b) the amino acid sequence in the polypeptide chain (c) the orientation of the amino acid side chains in space (d) the presence or absence of an α-helix
Last Answer : the amino acid sequence in the polypeptide chain
Description : Which of the following may characterize the “secondary structure” of proteins? (a) conformation of the protein backbone (b) α-Helix (c) parallel β-pleated sheet (d) all of the above
Last Answer : all of the above
Description : 9.The reason behind the anti-parallel strand of DNA is 1. Hydrogen bond 2. Ionic bond 3. Phosphodiester bond 4. Disulphide bond
Last Answer : Ans: Phosphodiester bond.
Description : Explain in brief about electrostatic bonds in antigen-antibody interaction ?
Last Answer : These are formed due to the attraction between opposite charged protein side chains.
Description : Hydrogen bonds are formed when a hydrogen atom is shared between two ____. a. molecules c. elements b. atoms d. neutrons
Last Answer : a. molecules
Description : Which of the following does not have disulphide bond? (A) Oxytocin (B) Vasopressin (C) Insulin (D) Glucagon
Description : This hormone has disulphide group: (A) Glucagon (B) Insulin (C) T4 (D) Epinephrine
Description : Human growth hormone has (A) One polypeptide chain and one intra-chain disulphide bond (B) One polypeptide chain and two intra-chain disulphide bond (C) Two polypeptide chains joined by one disulphide bond (D) Two polypeptide chains joined by two disulphide bond
Description : All the following statements about steroid hormones are true except (A) They are hydrophobic (B) They require carriers to transport them in circulation (C) Their receptors are intracellular (D) They require cyclic AMP as second messenger
Description : In the insulin molecule, the number of intrachain disulphide bridges is (A) 1 (B) 2 (C) 3 (D) 4
Description : In the insulin molecule, the number of interchain disulphide brides is (A) 1 (B) 2 (C) 3 (D) 4
Description : Amphiphatic lipids are (A) Hydrophilic (B) Hydrophobic (C) Both (A) and (B) (D) Lipophilic
Description : Lipoprotein present in cell membrane is by nature: (A) Hydrophilic (B) Hydrophobic (C) Both (A) and (B) (D) None of these