All α-amino acids give positive (A) Million’s test (B) Biurete test (C) Xanthproteic test (D) Ninhydrine test

1 Answer

Answer :

Answer : D

Related questions

Description : N-terminal amino acids of a polypeptide are estimated by (A) Edmann reaction (B) Sanger’s reagent (C) Formaldehyde test (D) Ninhydrine reaction

Last Answer : Answer : A

Description : Which of the following gives a positive Ninhydrin test? (A) Reducing sugar (B) Triglycerides (C) α-amino acids (D) Phospholipids

Last Answer : Answer : C

Description : Xanthoproteic test is positive in proteins containing (A) Sulphur amino acids (B) α-Amino acids (C) Aromatic amino acids (D) Aliphatic amino acids

Last Answer : Answer : C

Description : Will amino acids give a positive biuret test?

Last Answer : No. This needs a minimum of two peptide bonds.

Description : Thyroid stimulating hormone is a dimer. The α-subunits of TSH, LH, FSH are identical. Thus the biological specificity must therefore be β subunit in which the number of amino acids is (A) 78 (B) 112 (C) 130 (D) 199

Last Answer : Answer : B

Description : All of the following intermediates of citric acid cycle can be formed from amino acids except (A) α-Ketoglutarate (B) Fumarate (C) Malate (D) Oxaloacetate

Last Answer : Answer : C

Description : Thiamin diphosphate is required for oxidative decarboxylation of (A) α-Keto acids (B) α-Amino acids (C) Fatty acids (D) All of these

Last Answer : Answer : A

Description : All α-amino acids have one asymmetric carbon atom except (A) Arginine (B) Glycine (C) Aspartic acid (D) Histidine

Last Answer : Answer : B

Description : α-helix is disrupted by certain amino acids like (A) Proline (B) Arginine (C) Histidine (D) Lysine

Last Answer : Answer : A

Description : Each turn of α-helix contains the number of amino acids (A) 2.8 (B) 3.2 (C) 3.4 (D) 3.6

Last Answer : Answer : D

Description : Ninhydrin with evolution of CO2 forms a blue complex with (A) Peptide bond (B) α-Amino acids (C) Serotonin (D) Histamine

Last Answer : Answer : B

Description : Proteins contain (A) Only L- α - amino acids (B) Only D-amino acids (C) DL-Amino acids (D) Both (A) and (B)

Last Answer : Answer : A

Description : Million’s test is positive for (A) Phenylalanine (B) Glycine (C) Tyrosine (D) Proline

Last Answer : Answer : C

Description : Which one of the following is the correct matching of the site of action on the given substrate, the enzyme acting upon it and the end product? (a) Small intestine : Proteins Pepsin  →  ... Trypsin  →  Monoglycerides (d) Small intestine : Starch α-Amylase  →  Disaccharide (maltose)

Last Answer : (d) Small intestine : Starch α-Amylase  →  Disaccharide

Description : Amino acids are mostly synthesised from (a) mineral salts (b) fatty acids (c) volatile acids (d) α-ketoglutaric acid.

Last Answer : (d) α-ketoglutaric acid.

Description : Which of the following reactions is suitable for the preparation of α-amino acids? (a) Schmidt reaction (b) Hofmann's degradation of amides (c) Strecker's synthesis (b) Reduction of nitro compounds

Last Answer : Strecker's synthesis

Description : The α-carbon of all the amino acids is a chirality center except for __________. (a) Glycine (b) Threonine (c) Proline (d) Aspartic acid

Last Answer : Glycine

Description : The amino acids in which the R groups have a net positive charge at pH 7.0 are (A) Lysine, Arginine, Histidine (B) Lysine, Aspargine (C) Histidine, Aspargine (D) Glutamine, Arginine

Last Answer : Answer : A

Description : The true statement about solutions of amino acids at physiological pH is (A) All amino acids contain both positive and negative charges (B) All amino acids contain positively charged side chains ... amino acids contain only positive charge (D) All amino acids contain negatively charged side chains

Last Answer : Answer : A

Description : At neutral pH, a mixture of amino acids in solution would be predominantly: (A) Dipolar ions (B) Nonpolar molecules (C) Positive and monovalent (D) Hydrophobic

Last Answer : Answer : A

Description : The true statement about solutions of amino acids at physiological pH is (A) All amino acids contain both positive and negative charges (B) All amino acids contain positively charged side chains ... amino acids contain only positive Charge (D) All amino acids contain negatively charged side chains

Last Answer : (A) All amino acids contain both positive and negative charges

Description : At neutral pH, a mixture of amino acids in solution would be predominantly: (A) Dipolar ions (B) Nonpolar molecules (C) Positive and monovalent (D) Hydrophobic

Last Answer : (A) Dipolar ions

Description : Which of the following would give a positive Tollen’s test? (a) α-D-glucopyranose (b) methyl β-D-glucopyranoside (c) sucrose (d) methyl α-D-ribofuranoside

Last Answer : α-D-glucopyranose

Description : For synthesis of CTP and UTP, the amino group comes from (A) Amide group of Asparagine (B) Amide group of glutamine (C) α-Amino group of glutamine (D) α-Amino group of glutamate

Last Answer : Answer : B

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

Last Answer : Answer : A

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

Last Answer : Answer : C

Description : In the biosynthesis of the iron protoporphyrin, the product of the condensation between succinyl-CoA and glycine is (A) α-Amino β-ketoadipic acid (B) δ-Aminolevulinate (C) Hydroxymethylbilane (D) Uroporphyrinogen I

Last Answer : Answer : A

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 following ketoacid is involved in fixing dietary NH3 into amino acid: (A) Pyruvate (B) Oxalo acetate (C) Oxalo succinate (D) α-keto glutarate

Last Answer : Answer : B

Description : An amino acid that does not take part in α helix formation is (A) Histidine (B) Tyrosine (C) Proline (D) Tryptophan

Last Answer : Answer : C

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

Last Answer : Answer : A

Description : Each turn of α-helix contains the amino acid residues (number): (A) 3.6 (B) 3.0 (C) 4.2 (D) 4.5

Last Answer : Answer : A

Description : An example of α-amino acid not present in proteins but essential in mammalian metabolism is (A) 3-Amino 3-hydroxypropanoic acid (B) 2-Amino 3-hydroxybutanoic acid (C) 2-Amino 4-mercaptobutanoic acid (D) 2-Amino 3-mercaptopropanoic acid

Last Answer : Answer : C

Description : Decarboxylation of α-keto acids requires (A) Thiamine pyrophosphate, FAD, NAD+ (B) Flavin mononucleotide (C) NADP+ (D) NAD+ only

Last Answer : Answer : A

Description : The principal rate limiting step in the biosynthesis of bile acids is at the (A) 7-Hydroxylase reaction (B) 12 α-Hydroxylase reaction (C) Conjugation reaction (D) Deconjugation reaction

Last Answer : Answer : A

Description : The fatty acids containing even number and odd number of carbon atoms as well as the unsaturated fatty acids are oxidized by (A) α-oxidation (B) β-oxidation (C) ω-oxidation (D) All of these

Last Answer : Answer : B

Description : Fatty acids are oxidized by (A) α -oxidation (B) β -oxidation (C) ω -oxidation (D) All of these

Last Answer : Answer : D

Description : α-Oxidation of fatty acids occurs mainly in (A) Liver (B) Brain (C) Muscles (D) Adipose tissue

Last Answer : Answer : B

Description : All the following are omega-6-fatty acids except (A) Linoleic acid (B) α-Linolenic acid (C) γ-Linolenic acid (D) Arachidonic acid

Last Answer : Answer : B

Description : Give examples of derived amino acids.

Last Answer : Hydroxy proline, hydroxy lysine, ornithine, cit- rulline, homocysteine.

Description : Give the names of aromatic amino acids.

Last Answer : Phenylalanine and tyrosine.

Description : Give examples of amino acids with hydropho- bic side chains.

Last Answer : Valine, leucine, isoleucine.

Description : When cathode rays strike a target of high atomic weight, they give rise to – 1) α -rays (2) β and γ rays (3) X-rays (4) positive rays

Last Answer : (3) X-rays Explanation: When cathode rays strike a solid target of high atomic weight and high melting point such as tungsten, molybdenum, etc, they give rise to a highly pen-etrating radiation called the X-rays (LIT Physics by Dr. P.K Aganval).

Description : Calcium absorption is inferred by (A) Fatty acids (B) Amino acids (C) Vitamin D (D) Vitamin B12

Last Answer : Answer : A

Description : Degeneracy of the genetic code denotes the existence of (A) Base triplets that do not code for any amino acids (B) Codons consisting of only two bases (C) Codons that include one or more of the unusual bases (D) Multiple codons for a single amino acid

Last Answer : Answer : B

Description : Selectins are proteins that can recognise specific (A) Carbohydrates (B) Lipids (C) Amino acids (D) Nucleotides

Last Answer : Answer : A

Description : Glycoproteins are marked for destruction by removal of their (A) Oligosaccharide prosthetic group (B) Sialic acid residues (C) Mannose residues (D) N-terminal amino acids

Last Answer : Answer : D

Description : All the following statements about recognition of a codon on mRNA by an anticodon on tRNA are correct except (A) The recognition of the third base of the codon is not very precise (B) ... degeneracy of the genetic code (D) Wobble results in incorporation of incorrect amino acids in the protein

Last Answer : Answer : D

Description : All of the following statements about nonsense codons are true except (A) They do not code for amino acids (B) They act as chain termination signals (C) They are identical in nuclear and mitochondrial DNA (D) They have no complementary anticodons

Last Answer : Answer : C