1. Which description best matches biomolecules in living systems?
ⓐ. Natural organic compounds involved in life processes
ⓑ. Artificial polymers prepared mainly for industrial packaging
ⓒ. Inorganic salts present only as crystalline minerals
ⓓ. Metallic compounds formed during high-temperature reactions
Correct Answer: Natural organic compounds involved in life processes
Explanation: Biomolecules are mainly organic compounds found in living systems. They take part in essential biological functions such as energy supply, growth, repair, regulation, and heredity. Examples include carbohydrates, proteins, nucleic acids, vitamins, and hormones. The term does not refer to random industrial polymers or purely mineral salts, even though living organisms may also contain inorganic ions.
2. Which set contains only major biomolecule classes commonly studied in biomolecule chemistry?
ⓐ. Carbohydrates, alloys, vitamins, mineral salts
ⓑ. Proteins, nucleic acids, ceramics, mineral salts
ⓒ. Carbohydrates, proteins, vitamins, nucleic acids
ⓓ. Hydrocarbons, ores, catalysts, industrial detergents
Correct Answer: Carbohydrates, proteins, vitamins, nucleic acids
Explanation: Carbohydrates, proteins, vitamins, and nucleic acids are standard major classes of biomolecules. They are directly connected with nutrition, structure, metabolism, and genetic information. Hormones are also treated as biomolecules because they act as chemical messengers in living systems. Alloys, ceramics, ores, detergents, and ordinary industrial catalysts are not biomolecule classes.
3. Which biological role is most closely associated with nucleic acids?
ⓐ. Immediate heat insulation in skin
ⓑ. Heredity and genetic information
ⓒ. Formation of hard metallic deposits
ⓓ. Neutralisation of acids in the stomach only
Correct Answer: Heredity and genetic information
Explanation: Nucleic acids are biomolecules connected with heredity and protein synthesis. DNA stores genetic information and helps transmit it from one generation to another. RNA participates mainly in the expression of that information during protein formation. This role is different from simple energy storage or mineral deposition.
4. A compound is naturally present in cells and helps regulate growth, metabolism, or coordination even in very small amounts. Which biomolecule class best fits this description?
ⓐ. Carbohydrate
ⓑ. Protein fibre
ⓒ. Nucleic acid
ⓓ. Hormone
Correct Answer: Hormone
Explanation: Hormones are chemical messengers produced in living organisms and effective in very small quantities. They regulate processes such as growth, metabolism, and coordination. Their function is mainly regulatory rather than structural or hereditary. Carbohydrates are more closely linked with energy and storage, while nucleic acids are linked with genetic information.
5. Which pairing of biomolecule class and broad role is most appropriate?
ⓐ. Vitamins — primary genetic material
ⓑ. Carbohydrates — energy supply and storage
ⓒ. Nucleic acids — main body insulation fat
ⓓ. Hormones — large structural plant fibres
Correct Answer: Carbohydrates — energy supply and storage
Explanation: Carbohydrates commonly serve as energy-providing and energy-storing biomolecules. Glucose is a major energy source, while starch and glycogen act as storage carbohydrates. Vitamins are needed in small amounts for proper metabolic function but are not the main genetic material. Nucleic acids carry genetic information, and hormones regulate body processes.
6. Which statement correctly distinguishes biomolecules from ordinary non-living industrial chemicals?
ⓐ. Biomolecules are always inorganic and insoluble in water.
ⓑ. Biomolecules are defined only by their high melting points.
ⓒ. Biomolecules occur in living systems and support life.
ⓓ. Biomolecules are metals extracted from biological ores.
Correct Answer: Biomolecules occur in living systems and support life.
Explanation: Biomolecules are identified by their occurrence and function in living systems. They include compounds that help organisms obtain energy, build structures, regulate processes, and pass hereditary information. They are not defined only by a physical property such as melting point. Many biomolecules are organic compounds, so calling them always inorganic would be misleading.
7. Which biomolecule class is most directly associated with growth, repair, enzymes, and structural components such as collagen or keratin?
ⓐ. Proteins
ⓑ. Nucleic acids
ⓒ. Vitamins
ⓓ. Hormones
Correct Answer: Proteins
Explanation: Proteins are nitrogen-containing biomolecules built from amino acids. They are essential for growth, repair, structure, and many biological functions. Enzymes are mostly proteins and act as biological catalysts. Collagen and keratin are examples of structural proteins, so this role fits proteins better than vitamins or nucleic acids.
8. A student says, “All biomolecules mainly provide energy.” Which response best corrects this statement?
ⓐ. The statement is accurate because every biomolecule is a fuel.
ⓑ. The statement is incomplete because biomolecule roles vary.
ⓒ. The statement is accurate only for vitamins and hormones.
ⓓ. The statement is wrong because no biomolecule provides energy.
Correct Answer: The statement is incomplete because biomolecule roles vary.
Explanation: Some biomolecules, especially carbohydrates and fats, are strongly connected with energy supply or storage. However, many biomolecules perform other major functions. Proteins may provide structure or catalyse reactions, nucleic acids handle genetic information, vitamins support metabolic processes, and hormones regulate body activities. Therefore reducing all biomolecules to energy providers gives an incomplete view.
9. Which option best identifies the dominant broad function of vitamins?
ⓐ. They form the main hereditary material in chromosomes.
ⓑ. They act as micronutrients needed for normal metabolism.
ⓒ. They make long chains of amino acids for muscle fibres.
ⓓ. They store glucose units in plant storage tissues.
Correct Answer: They act as micronutrients needed for normal metabolism.
Explanation: Vitamins are organic micronutrients required in small amounts for normal growth and metabolic functioning. They usually do not serve as the main energy source. Their deficiency can lead to specific disorders because they support essential biochemical processes. Heredity is mainly linked with nucleic acids, while long amino-acid chains describe proteins.
10. Which of the following is the best reason biomolecules are studied as a connected group?
ⓐ. They all have exactly the same structure and function.
ⓑ. They are all simple gases with similar physical properties.
ⓒ. They all contain only carbon and hydrogen atoms.
ⓓ. They support essential life processes.
Correct Answer: They support essential life processes.
Explanation: Biomolecules are grouped together because they are chemically important in living systems. Their structures and functions are not identical, but each class contributes to life processes in a specific way. Carbohydrates, proteins, nucleic acids, vitamins, and hormones differ widely in composition and role. Their connection lies in biological importance, not in having the same formula or physical state.
11. Which classification is most suitable for a biomolecule that mainly controls hereditary information and protein synthesis?
ⓐ. Nucleic acid
ⓑ. Carbohydrate
ⓒ. Vitamin
ⓓ. Steroid hormone
Correct Answer: Nucleic acid
Explanation: Nucleic acids are the biomolecules most directly involved in heredity and protein synthesis. DNA stores hereditary information, while RNA helps use that information during protein formation. Carbohydrates are mainly connected with energy and storage roles. Vitamins and hormones are important regulatory or supportive biomolecules, but they are not the main carriers of genetic information.
12. Which statement gives the most balanced view of biomolecules?
ⓐ. They are mostly laboratory-made substances with no natural biological role.
ⓑ. They include only carbohydrates because living cells mainly need energy.
ⓒ. They include classes with energy, structure, regulation, and heredity roles.
ⓓ. They are all inorganic nutrients required in kilogram quantities.
Correct Answer: They include classes with energy, structure, regulation, and heredity roles.
Explanation: Biomolecules include several major classes rather than only one type of compound. Carbohydrates are important for energy, proteins for growth and structure, vitamins for metabolic support, hormones for regulation, and nucleic acids for heredity. These roles show why biomolecules are central to living systems. Calling them all inorganic or laboratory-made ignores their natural biological occurrence.
13. Which set best matches broad biomolecule classes with their usual biological roles?
ⓐ. Carbohydrates—heredity; vitamins—main storage polymers; proteins—only pigments
ⓑ. Proteins—catalysis and structure; carbohydrates—energy; nucleic acids—heredity
ⓒ. Nucleic acids—energy storage; hormones—structural fibres; carbohydrates—enzymes
ⓓ. Vitamins—large genetic polymers; proteins—mineral salts; hormones—food reserves
Correct Answer: Proteins—catalysis and structure; carbohydrates—energy; nucleic acids—heredity
Explanation: Proteins often act as enzymes and structural materials, while carbohydrates commonly provide or store energy. Nucleic acids are linked with storage and transfer of genetic information. Vitamins help normal metabolism in small quantities but are not large storage polymers. Hormones mainly regulate body processes and are not usually classified as food reserves.
14. A biomolecule contains carbon, hydrogen, oxygen, nitrogen, and phosphorus and is mainly linked with hereditary information. Which class does it most likely belong to?
ⓐ. Nucleic acids
ⓑ. Carbohydrates
ⓒ. Simple lipids
ⓓ. Vitamins
Correct Answer: Nucleic acids
Explanation: Nucleic acids contain carbon, hydrogen, oxygen, nitrogen, and phosphorus. Their phosphate groups account for the presence of phosphorus, while nitrogenous bases account for nitrogen. DNA and RNA are the two main nucleic acids. Their major biological role is connected with heredity and protein synthesis.
15. Which comparison between carbohydrates and proteins is most accurate?
ⓐ. Both are mainly hereditary polymers with phosphate backbones.
ⓑ. Carbohydrates are mainly amino-acid polymers, while proteins are sugar polymers.
ⓒ. Carbohydrates often supply energy, while proteins are built from amino acids.
ⓓ. Both are always vitamins required only in trace quantities.
Correct Answer: Carbohydrates often supply energy, while proteins are built from amino acids.
Explanation: Carbohydrates commonly function as energy sources or storage materials. Proteins are polymers of amino acids and often contain nitrogen. Their roles include growth, repair, structure, and enzymatic catalysis. A phosphate backbone is characteristic of nucleic acids rather than carbohydrates or proteins.
16. Which biomolecule class is most closely associated with enzymes in living systems?
ⓐ. Carbohydrates
ⓑ. Proteins
ⓒ. Vitamins
ⓓ. Nucleic acids
Correct Answer: Proteins
Explanation: Most enzymes are proteins, although not every protein is an enzyme. Proteins have folded structures that allow specific binding and catalytic activity. Their amino-acid sequence and three-dimensional shape are important for function. Carbohydrates mainly provide or store energy, while nucleic acids store and express genetic information.
17. Which statement correctly describes vitamins as a biomolecule class?
ⓐ. They are required in small amounts and support normal metabolism.
ⓑ. They are long polymers that store hereditary information.
ⓒ. They are always large structural proteins in connective tissue.
ⓓ. They are the main energy reserve stored as starch in animals.
Correct Answer: They are required in small amounts and support normal metabolism.
Explanation: Vitamins are organic compounds needed in small quantities for normal body functions. They generally do not provide significant energy like carbohydrates. Their deficiency can cause specific disorders because many metabolic processes depend on them. They are not nucleic-acid polymers, structural proteins, or starch-like storage materials.
18. Which reverse mapping is most appropriate?
ⓐ. Storage of genetic information \(\rightarrow\) carbohydrate
ⓑ. Low-concentration chemical regulation \(\rightarrow\) hormone
ⓒ. Main plant storage sugar polymer \(\rightarrow\) nucleic acid
ⓓ. Enzyme-like catalytic protein \(\rightarrow\) vitamin
Correct Answer: Low-concentration chemical regulation \(\rightarrow\) hormone
Explanation: Hormones act as chemical messengers and regulate body processes even at low concentrations. Their effects may involve growth, metabolism, reproduction, or coordination. Carbohydrates are more closely related to energy storage and supply. Nucleic acids deal with genetic information, and enzymes are mostly proteins rather than vitamins.
19. Which class-wise element clue is most useful for identifying proteins rather than ordinary carbohydrates?
ⓐ. Frequent presence of nitrogen
ⓑ. Complete absence of carbon
ⓒ. Mandatory presence of phosphorus
ⓓ. Exclusive presence of metals
Correct Answer: Frequent presence of nitrogen
Explanation: Proteins are polymers of amino acids, and amino acids contain an amino group. This makes nitrogen a characteristic element in proteins. Ordinary carbohydrates are mainly composed of carbon, hydrogen, and oxygen. Phosphorus is especially important in nucleic acids because of phosphate groups, not as the usual defining clue for proteins.
20. A sample is described as a polymer made of units that help determine hereditary traits. Which biomolecule class is being described?
ⓐ. Carbohydrate
ⓑ. Protein
ⓒ. Nucleic acid
ⓓ. Hormone
Correct Answer: Nucleic acid
Explanation: A polymer connected with hereditary traits points to nucleic acids. DNA is a polymer of deoxyribonucleotides and stores genetic information. RNA is also a nucleic acid and participates in protein synthesis. Proteins are polymers too, but their monomer units are amino acids and their main role is not direct hereditary storage.
