Biomolecules MCQs

Which of the following statements regarding the acid-soluble pool and acid-insoluble fraction are correct?

I. Grinding living tissue in trichloroacetic acid (Cl₃CCOOH) yields a slurry that filters into an acid-soluble pool and an acid-insoluble retentate.
II. The acid-soluble pool contains organic compounds with molecular weights ranging from 18 to around 800 Daltons.
III. Biomacromolecules in the acid-insoluble fraction have molecular weights strictly below 1,000 Daltons.
IV. Inorganic ions like sulphate and phosphate are present in the acid-soluble fraction.

Which of the above statements are correct?

Which of the following statements regarding amino acid substituent groups and R-group diversity are correct?

I. Amino acids are substituted methanes containing four substituent groups on the α-carbon.
II. Glycine has hydrogen as its R-group, while alanine has a methyl group.
III. Serine contains a hydroxy methyl group (-CH₂OH) as its variable R-group.
IV. Valine is an acidic amino acid, while glutamic acid is a neutral amino acid.

Which of the above statements are correct?

Which of the following statements regarding zwitterionic amino acid chemistry and aromatic amino acids are correct?

I. Tyrosine, phenylalanine, and tryptophan are classified as aromatic amino acids.
II. Lysine is a basic amino acid.
III. The zwitterionic form of an amino acid carries both positive and negative charges simultaneously.
IV. At extremely low pH, amino acids carry a net negative charge due to complete loss of protons from -NH₃⁺ groups.

Which of the above statements are correct?

Which of the following statements regarding fatty acid structure and carbon numbering are correct?

I. Arachidonic acid has 20 carbon atoms including the carboxyl carbon.
II. Palmitic acid has 16 carbon atoms including the carboxyl carbon.
III. Saturated fatty acids possess one or more carbon-carbon double bonds.
IV. Glycerol is chemically trihydroxy propane.

Which of the above statements are correct?

Which of the following statements regarding glycerides, fats, oils, and phospholipids are correct?

I. Fatty acids esterified with glycerol form monoglycerides, diglycerides, and triglycerides.
II. Oils have lower melting points than fats (e.g., gingelly oil) and remain liquid in winter.
III. Lecithin is a phospholipid containing a phosphorylated organic compound present in cell membranes.
IV. Phospholipids are true polymeric biomacromolecules with molecular weights of 50,000 Daltons.

Which of the above statements are correct?

Which of the following statements regarding purines, pyrimidines, nucleosides, and nucleotides are correct?

I. Adenine and Guanine are substituted purines with heterocyclic double rings, while Cytosine, Uracil, and Thymine are pyrimidines.
II. Adenosine, Guanosine, Cytidine, Uridine, and Thymidine are nucleosides.
III. Adenylic acid, Guanylic acid, and Thymidylic acid are nucleotides.
IV. Uracil is found exclusively in DNA, while Thymine is restricted to RNA.

Which of the above statements are correct?

Which of the following statements regarding primary vs. secondary metabolite classifications are correct?

I. Primary metabolites have identifiable physiological functions in host organisms.
II. Morphine and codeine are secondary metabolites categorized as alkaloids.
III. Abrin and ricin are secondary metabolites categorized as toxins.
IV. Concanavalin A is categorized as a drug, while vinblastin is a lectin.

Which of the above statements are correct?

Which of the following statements regarding secondary metabolite categories (terpenoids, essential oils, polymeric substances) are correct?

Statement I: Monoterpenes and diterpenes belong to terpenoids.
Statement II: Lemon grass oil is an essential oil belonging to secondary metabolites.
Statement III: Carotenoids and anthocyanins are secondary metabolites classified as pigments.
Statement IV: Rubber, gums, and cellulose are secondary metabolites classified as alkaloids.

Which of the following statements regarding cellular mass percentage distribution (NCERT Table 9.4) are correct?

Statement I: Water is the most abundant chemical in cells, making up 70–90% of total cellular mass.
Statement II: Proteins constitute 10–15% of total cellular mass.
Statement III: Nucleic acids constitute 5–7% of total cellular mass, while carbohydrates constitute 3%.
Statement IV: Lipids constitute 15% of cellular mass, while ions constitute 10%.

Which of the following statements regarding protein polypeptide structure and amino acid essentiality are correct?

Statement I: Proteins are linear chains of amino acids linked together by peptide bonds.
Statement II: Proteins are heteropolymers of 20 types of amino acids.
Statement III: Essential amino acids can be synthesized in human tissues from glucose.
Statement IV: Collagen is the most abundant protein in the animal world.