Description : A molecule of CO2 is captured by biotin when it acts as coenzyme for carboxylation reaction. The carboxyl group is covalently attached to (A) A nitrogen (N1) of the biotin molecule (B) Sulphur of thiophene ring (C) α-Amino group of lysine (D) α-Amino group of protein
Last Answer : Answer : A
Description : In biotin-containing enzymes, the biotin is bound to the enzyme by (A) An amide linkage to carboxyl group of glutamine (B) A covalent bond with CO2 (C) An amide linkage to an amino group of lysine (D) An amide linkage to α-carboxyl group of protein
Last Answer : Answer : C
Description : The nucleophilic attack on the esterified carboxyl group of the peptidyl-tRNA occupying the P site and the α-amino group of the new amino acyl tRNA, the number of ATP required by the amino acid on the charged tRNA is (A) Zero (B) One (C) Two (D) Four
Description : The α-amino group of the new amino acyl tRNA in the A site carries out a nucleophilic attack on the esterified carboxyl group of the peptidyl tRNA occupying the P site. This reaction is catalysed by (A) DNA polymerase (B) RNA polymerase (C) Peptidyl transferase (D) DNA ligase
Description : The enzyme amino acyl tRNA synthetase is involved in (A) Dissociation of discharged tRNA from 80S ribosome (B) Charging of tRNA with specific amino acids (C) Termination of protein synthesis (D) Nucleophilic attack on esterified carboxyl group of peptidyl tRNA
Last Answer : Answer : B
Description : The active site of an enzyme is formed by a few of the enzymes: (A) R groups of the amino acids (B) Amino groups of the amino acids (C) Carboxyl group of the amino acids (D) Exposed sulfur bonds
Description : The central heavy metal cobalt of vitamin B12 is coordinately bound to (A) Cyanide group (B) Amino group (C) Carboxyl group (D) Sulphide group
Description : A functional group designated—COOH is known as a/an a. Carboxyl. b. Carbonyl. c. Amino. d. Hydroxyl.
Last Answer : a. Carboxyl.
Description : From two amino acids peptide bond formation involves removal of one molecule of (A) Water (B) Ammonia (C) Carbondioxide (D) Carboxylic acid
Description : Which of the following statement(s) is/are true concerning translation of the mRNA message to protein synthesis? a. An adaptor molecule, tRNA, recognizes specific nucleic acid bases and unites them ... and the free amino acid occurs in the free cytoplasm d. Complete protein synthesis takes hours
Last Answer : Answer: a, b The synthesis of protein involves conversion from a four-letter nucleotide language to one of 20 chemically distinct amino acids. This process is referred to as ... translation and be moving down the mRNA molecules simultaneously, thus increasing the rate of protein synthesis
Description : Agonists affect the receptor molecule in the following manner: A. Alter its amino acid sequence B. Denature the receptor protein C. Alter its folding or alignment of subunits D. Induce covalent bond formation
Last Answer : C. Alter its folding or alignment of subunits
Description : What bond links amino acids together? -Biology
Last Answer : answer:
Description : α-Oxidation i.e., the removal of one carbon at a time from the carboxyl end of the molecule has been detected in (A) Brain tissue (B) Liver (C) Adipose tissue (D) Intestine
Description : Glycine is a unique amino acid because it (a) has no chiral carbon (b) has a sulfur containing R group (c) cannot form a peptide bond (d) is an essential amino acid
Last Answer : has no chiral carbon
Description : The greater acidity of carboxylic acids compared to alcohols arises primarily from : (a) the electron-donating effect of the hydroxyl group (b) the electron-withdrawing effect of the carboxyl ... of α-hydrogens of carboxylic acids (d) the resonance stability associated with the carboxylate ion
Last Answer : the resonance stability associated with the carboxylate ion
Description : Which one of the following biomolecules is correctly characterized? (a) Lecithin-a phosphorylated glyceride found in cell membrane. (b) Palmitic acid - an unsaturated fatty acid with 18 carbon atoms. ... Alanine amino acid - contains an amino group and an acidic group anywhere in the molecule.
Last Answer : (a) Lecithin-a phosphorylated glyceride found in cell membrane
Description : Enamine contains ……. a. double bond and amino group b. double bond and alcohol c. dounle bond and amide d. Diamines
Last Answer : a. double bond and amino group
Description : The carboxyl functional group (-COOH) is present in
Last Answer : The carboxyl functional group (-COOH) is present in A. picric acid B. barbituric acid C. ascorbic acid D. aspirin
Description : Which does not have a carboxyl group?
Last Answer : Which does not have a carboxyl group? A. Picric acid B. Ethanoic acid C. Aspirin D. Benzoic acid
Description : Niacin contains a (A) Sulphydryl group (B) Carboxyl group (C) Amide group (D) All of these
Description : Reducing ability of carbohydrates is due to (A) Carboxyl group (B) Hydroxyl group (C) Enediol formation (D) Ring structure
Last Answer : A
Description : During each cycle of β-oxidation (A) One carbon atom is removed from the carboxyl end of the fatty acid (B) One carbon atom is removed from the methyl end of the fatty acid (C) Two carbon atoms ... carboxyl end of the fatty acid (D) Two carbon atoms are removed from the methyl end of the fatty acid
Description : Arrange the following carboxyl compounds in increasing order of their reactivity in nucleophilic addition reactions. Explain with proper reasoning : Benzaldehyde. p-tolualdeyde, p-nitrobenzaldehyde, Acetophenone.
Last Answer : Ans. Acetophenone is a ketone while all others are aldehydes, therefore it is least reactive. In p-tolualdehyde, there is methyl group (CH3 ) at para position w.r.t. to the ... overall order of increasing reactivity : acetophenone < p-tolualdehyde < benzaldehyde < p-nitrobenzaldehyde.
Description : Digestion of proteins involves (a) changes in secondary structure only (b) cleavage of peptide linkages (c) removal of all carboxyl groups in the form of CO2. (d) removal of all NH2 groups in the form of NH3
Last Answer : cleavage of peptide linkages
Description : Mineral acids are also classified as: w) carboxyl acids x) inorganic acids y) non-electrolytic acids z) oxidation acids
Last Answer : ANSWER: X -- INORGANIC ACIDS
Description : Can the amino group, in the aniline molecule, become meta-directing in an electrophilic substitution reaction ?
Last Answer : Can the amino group, in the aniline molecule, become meta-directing in an electrophilic substitution reaction ... D. Yes, in a non-polar solvent
Description : What kind of bond is formed when the attraction between the hydrogen atom in one water molecule and the oxygen molecule in another?
Last Answer : Feel Free to Answer
Description : An unknown amino acid has `0.32%` sulphur by mass . If each molecule has one sulphur atom only 1 g of amino acid has . . . . . . . Molecules :-
Last Answer : An unknown amino acid has `0.32%` sulphur by mass . If each molecule has one sulphur atom only 1 g of amino ... C. `6.02xx10^(24)` D. `6.02xx10^(23`
Description : Which is a basic unit of a sugar molecule monosaccharide amino acid fatty acid nucleotide?
Last Answer : Monosaccharide
Description : Degeneracy of genetic code implies that (A) Codons do not code for specific amino acid (B) Multiple codons must decode the same amino acids (C) No anticodon on tRNA molecule (D) Specific codon decodes many amino acids
Description : In the B chain of insulin molecule, the C-terminal amino acid: (A) Threonine (B) Tyrosine (C) Glutamate (D) Valine
Description : In the B chain of insulin molecule, the Nterminal amino acid is (A) Proline (B) Threonine (C) Phenylalanine (D) Lysine
Description : In the A chain of insulin molecule the Cterminal amino acid is (A) Asparagine (B) Threonine (C) Valine (D) Tyrosine
Description : In A chain of the insulin molecule the Nterminal amino acid is (A) Glycine (B) Valine (C) Serine (D) Phenylalanine
Description : At a pH below the isoelectric point, an amino acid exists as (A) Cation (B) Anion (C) Zwitterion (D) Undissociated molecule
Description : Assertion `:` Pancreatic amylase digest protein to amino acid. Reason `:` Pancreatic amylase breaks the peptide bond of protein.
Last Answer : Assertion `:` Pancreatic amylase digest protein to amino acid. Reason `:` Pancreatic amylase breaks the ... D. If both Assertion & Reason are false.
Description : How many high-energy phosphate bond equivalents are required for amino acid activation in protein synthesis? (A) One (B) Two (C) Three (D) Four
Description : An amino acid which contains a disulphide bond is (A) Lysine (B) Methionine (C) Homocysteine (D) Cystine
Last Answer : Answer : D
Description : The covalent bond that is repeatedly present between different amino acid residues in a protein is called (a) p-bond (b) hydrogen bond (c) peptide bond (d) metallic bond
Last Answer : Ans:(c)
Description : Amino acid containing a thio-ether bond is.
Last Answer : Methionine.
Description : Which of the following step of translation does not consume a high energy phosphate bond? (a) Peptidyl transferase reaction (b) Aminoacyl tRNA binding to A-site (c) Translocation (d) Amino acid activation
Last Answer : (b) Aminoacyl tRNA binding to A-site
Last Answer : (a) Peptidyl transferase reaction
Description : What happens when a chemical bond is formed? (1) energy is always absorbed (2) energy in always released (3) more energy is released than is absorbed (4) energy is neither released nor ... as potential energy. Upon the breaking of these bonds the energy is released thereby creating usable energy.
Last Answer : Silver nitrate solution is kept in brown bottles in laboratory because - (1) it reacts with ordinary white bottles (2) brown bottles stops the passage of light through it (3) brown bottles do not react with it (4) brown bottles react with it
Description : In an oxygen molecule, two atoms are united by - (1) one bond (2) two bonds (3) three bonds (4) four bonds
Last Answer : (2) two bonds Explanation: Two oxygen atoms can both achieve stable structures by sharing two pairs of electrons as in the diagram. Two electrons of each of the atom in the oxygen molecule ... is shown conventionally by two lines joining the atoms. Each line represents one pair of shared electrons.
Description : How many hydrogen-bonded water molecule(s) are present in CuSO4.5H2O ? Draw its structure to show formation of hydrogen bond.
Last Answer : Ans- one molecule of water is bonded by hydrogen bond and is deeply embedded in the lattice, While four molecules are bonded with coordinate bond. [ Cu(H2O)4] SO4.H2O
Description : Is the bond energy of all the four C-H bonds in CH4 molecule equal? If not then why ? How is C-H bond energy then reported?
Last Answer : Ans. No because after breaking of C-H bonds one by one, the electronic environments change. The reported value is the average of of the bond dissociation energies of the four C-H bonds.
Description : Explain the formation of H2 molecule on the basis of valence bond theory.
Last Answer : Ans. When two H atoms come closer the following forces operate between them: a. Attractive : i.nucleus of atom and its electron ii.nucleus of one atom and electron of other. b.repulsive ... and the system acquires minimum energy .At this stage two hydrogen atoms are said to be bonded together.
Description : Which of the following statements are false about benzene? (a) It is a planar molecule with bond angles 120°. (b) It is immiscible with water forming the lower layer. (c) It can be ... Ni catalyst. (d) It reacts with ethyl chloride in the presence of aluminium chloride to form ethylbenzene.
Last Answer : It is immiscible with water forming the lower layer
Description : Which of the following statements about benzene is correct? (a) All of the carbon atoms are sp3 hybridized. (b) It has no delocalized electrons. (c) The carbon-carbon bond length is longer than that of ethane. (d) It is a planar molecule.
Last Answer : It is a planar molecule.