Which of the following statements is correct about physical properties of water? a. The heat of sublimation of ice is lower that heat of fusion. b. Boling points of H₂O and CH₄ are same as their molecular weight is same.c. Water at 0^oC has a distance of 2.82-Å in neighbor molecules and 2.76-Å in ice form.

Which of the following statements is/are correct about amino acids?

1. Alanine, valine, leucine, and isoleucine have aromatic hydrocarbon side chains.
2. Methionine has a thiol ether side chain that resembles an n-butyl group in many of its physical properties.
3. Proline has conformational constraints imposed by the cyclic nature of its pyrrolidine side chain.

Which of the following annotations on chemical nature of amino acids is/are correct?

1. Phenylalanine has indole group.
2. Tryptophan has phenyl group.
3. Tyrosine has phenol group.

Which of the following options is the correct order of dipole moment and dielectric constant of the following solvents?

Which of the following amino acids have uncharged polar amide side chains?

1. Serine 2. Threonine 3. Asparagine 4. Glutamine 5. Tyrosine

Which of the following amino acids and the characters are correctly matched?

1. cysteine: charged: thiol group 2. lysine: uncharged: butylammonium side chain 3. arginine: uncharged: guanidino group 4. histidine: uncharged: imidazolium group

Which of these statements is/are correct about operational classification of amino acids based on optical activity?

1. Dextrorotatory rotate the plane of plane-polarised light clockwise.
2. Levorotatory rotate the plane of plane-polarised light anticlockwise
3. Dextrorotatory and levorotatory molecules are assigned negative and positive values, respectively.

Which of the following statements about the Fischer convention of amino acids nomenclature is/are correct?

1. This configuration system of the groups was introduced about an asymmetric center of aspirin.
2. Horizontal bonds extend above and vertical bonds extend below the plane of the paper.
3. All amino acids derived from proteins have the L-stereochemical configuration.

Which of the following statements about some uncommon amino acid residues is/are correct?

1. Amino acid residues- 4-hydroxyproline and 5-hydroxylysine are important structural constituents of collagen.
2. Histones have specifically methylated, acetylated, and/or phosphorylated Lys, Arg and Ser residues.
3. N-formylmethionine is initially the N-terminal residue of all prokaryotic proteins.
4. Gamma-carboxyglutamic acid is a constituent of several proteins involved in blood clotting.

Which of these statements about Cahn–Ingold–Prelog system of amino acids nomenclature is/are correct?

1. Atoms of higher atomic number bonded to a chiral center are ranked below those of lower atomic number.
2. The order of priority of these functional groups is: SH < OH < NH_2. 3. The order of priority of these functional groups is: CH₂OH < C₆H₅ < CH_3.

Find the correct match of amino acid residue with its function.

1. Gamma-aminobutyric acid: a glutamatedecarboxylation product: neurotransmitters
2. Dopamine: tyrosine derivative: fatty acid metabolism intermediate
3. Histamine: histidine decarboxylation product: local mediator of allergic reactions
4. Thyroxine: a tryptophan derivative: an iodine-containing thyroid hormone

Certain amino acids are important intermediates in various metabolic processes. A is an intermediate in urea biosynthesis, B is an intermediate in amino acid metabolism, C is a biological methylating reagent, D is an antibiotic and E is a neurotransmitter.

Which of the following systems is/are not a nucleotide database?

1. GenBank
2. DDBJ
3. EMBL
4. DNASTAR

Which of the following statements about thalidomide is/are correct?

1. It was widely used in Europe as a mild laxtive in the early 1960s.
2. Its active enantiomer causes severe birth defects in humans.
3. Its effect is most dangerous during the last trimester of pregnancy.
4. It was often prescribed to alleviate nausea (morning sickness) that is common during pregnancy.

What is the correct order of ion mobility of the following ions in an aqueous solution?