Biomolecules and Enzymes

VAST (Vector Alignment Search Tool) is NCBI's structure comparison service that identifies similar protein 3D structures by comparing structural geometry and topology. DALI is a similar tool but not part of NCBI, LUDI is for drug design, and BLAST is for sequence similarity.

VADAR (Volume, Area, Dihedral Angle Reporter) is a comprehensive protein structure validation tool that analyzes stereochemical quality, geometry, and other structural parameters. Alignment tools (option A) are for sequence comparison, and structure prediction tools (option B) generate models rather than validate them.

Pratt is a tool for ab initio protein function prediction that derives function directly from sequence without relying on homology. ProtFun and PFP Server are also function prediction tools, but the question specifically asks about ab initio prediction from sequence alone, which is Pratt's specialization.

MarvinSpace, RasMol, and Swiss-PDB Viewer are all established 3D molecular visualization tools used for viewing protein structures and molecular models.

UniProt, PIR, and Swiss-Prot are all protein sequence databases. UniProt is the universal protein resource, PIR is the Protein Information Resource, and Swiss-Prot is a high-quality manually annotated protein database. Therefore 'All of the above' is correct.

 Competitive inhibition is seen when the substrate and the inhibitor compete for the active site on the enzymes. Most competitive inhibitors function by binding reversibly to the active site of the enzyme. As a result, many sources state that this is the defining feature of competitive inhibitors.

Enzymes, vitamins and hormones can be classified into a single category of biological chemicals because all of these help in regulating metabolism.

The simplest and smallest amino acid found in proteins is glycine, for which the R-group is a hydrogen (H).

This option is correct because Methionine is an α-amino acid with the chemical formula HO₂CCH (NH₂) CH₂CH₂SCH₃. This essential amino acid is classified as non-polar essential amino acid and Alginic acids (Alginates) found in algae is a water insoluble dietary fiber.

This is the correct statement. P, Q and R all are essential amino acids for humans. The indispensable amino acids or essential amino acids are those amino acids that cannot be synthesized by the organism being considered, and therefore must be supplied in its diet. The amino acids regarded as essential for humans are phenylalanine, valine, threonine, tryptophan, isoleucine, methionine, leucine, lysine, and histidine. The amino acids arginine, cysteine, glycine, glutamine, proline, serine and tyrosine are considered as conditionally essential amino acids, meaning they are not normally required in the diet, but must be supplied exogenously to specific populations that do not synthesize them in adequate amounts.

This is the correct option as the correct matching is P - 3, Q - 5, R - 1, S - 4. Histidine is alpha amino acid. The conjugate acid of the imidazole side chain. Leucine is a branched-chain α-amino acid with the chemical formula HO₂CCH (NH₂) CH₂CH (CH₃)₂.  Leucine is hydrophobic in nature dut to the presence of aliphatic isobutyl side chain. Threonine is an α-amino acid with the chemical formula HO₂CCH (NH₂) CH (OH )CH₃. This essential amino acid is classified as polar. Together with serine, threonine is one of two proteinogenic amino acids bearing an alcohol group (OH group). Tryptophan is one of the 22 standard amino acids and is an essential amino acid in the human diet. It has indole as fuctional group.

The protein casein is present in milk.

Ornithine and Citrulline: Non-protein amino acids.

Amino acids and sugar

Sulphur is present in 2 amino acids cysteine and methionine.