Chemical Composition & Metabolites — NEET Biology MCQs with Solutions
Free NEET Biology Chemical Composition & Metabolites MCQs with step-by-step solutions (6 questions). Part of Biomolecules. Practise online on Prepizo — no login needed.
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Questions with solutions
Q1 — Chemical Composition & Metabolites · easy · theory
Compounds with molecular weight less than ~1000 Da found in the acid-soluble pool are called:
A. Polymers only
B. Macromolecules
C. Micromolecules (e.g. sugars, amino acids) ✓ Correct
D. Enzymes
Solution: Micromolecules (mol. wt < 1000 Da) form the acid-soluble pool; macromolecules (> 10 kDa) are in the acid-insoluble fraction.
Q2 — Chemical Composition & Metabolites · easy · theory
Alkaloids, flavonoids, rubber and essential oils are examples of:
A. Primary metabolites
B. Secondary metabolites ✓ Correct
C. Enzymes
D. Biomacromolecules
Solution: Secondary metabolites have no obvious direct role in normal physiology but are useful (drugs, pigments, defence).
Q3 — Chemical Composition & Metabolites · medium · theory
Amino acids, glucose, nucleotides and fatty acids are examples of:
A. Non-biological molecules
B. Only macromolecules
C. Secondary metabolites
D. Primary metabolites ✓ Correct
Solution: Primary metabolites have identifiable functions in normal physiological processes.
Q4 — Chemical Composition & Metabolites · medium · theory
The most abundant chemical in a living cell (and the medium of biochemical reactions) is:
A. Water ✓ Correct
B. Protein
C. Carbohydrate
D. Lipid
Solution: Water constitutes ~70–90% of cell mass and is the most abundant molecule; proteins are the most abundant macromolecule.
Q5 — Chemical Composition & Metabolites · hard · theory
When living tissue is ground with trichloroacetic acid and filtered, proteins, nucleic acids and polysaccharides are found in the:
A. Acid-soluble filtrate
B. Ash only
C. Acid-insoluble (retentate) fraction ✓ Correct
D. Gaseous phase
Solution: Macromolecules (proteins, nucleic acids, polysaccharides, lipids) form the acid-insoluble pool; micromolecules pass into the filtrate.
Q6 — Chemical Composition & Metabolites · hard · theory
Lipids, though sometimes below 800 Da, are found in the acid-INSOLUBLE (macromolecular) fraction because:
A. They have very high molecular weight
B. They dissolve in acid
C. They form part of membranes and come down as vesicles, not truly free molecules ✓ Correct
D. They are true polymers
Solution: Membrane lipids sediment as vesicular structures with the macromolecular fraction, an exception to the size rule.