Unit 4 Chapter 9: Biomolecules — Online MCQ Test
BOTANY · CLASS 11 INTERMEDIATE 1 YEAR · Telangana State Board
Practice Unit 4 Chapter 9: Biomolecules with a free chapter-wise online MCQ test.
This chapter covers: This chapter covers primary and secondary metabolites chemical structure and properties of carbohydrates proteins amino acids lipids nucleic acids and enzyme mechanisms..
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Unit 4 Chapter 9: Biomolecules — Important Questions & Answers
Which of the following is an example of a primary metabolite?
- A. Alkaloid
- B. Protein
- C. Terpenoid
- D. Pigment
Answer: B. Protein
Proteins are primary metabolites because they are directly involved in growth and normal metabolism. Alkaloids, terpenoids, and pigments are secondary metabolites.
Proteins are primary metabolites because they are directly involved in growth and normal metabolism. Alkaloids, terpenoids, and pigments are secondary metabolites.
The basic structural unit of proteins is:
- A. Fatty acid
- B. Monosaccharide
- C. Amino acid
- D. Nucleotide
Answer: C. Amino acid
Proteins are polymers made up of amino acids joined by peptide bonds. Other choices are building blocks of lipids, carbohydrates, and nucleic acids respectively.
Proteins are polymers made up of amino acids joined by peptide bonds. Other choices are building blocks of lipids, carbohydrates, and nucleic acids respectively.
Which of the following monosaccharides is a hexose?
- A. Ribose
- B. Glucose
- C. Glyceraldehyde
- D. Erythrose
Answer: B. Glucose
Glucose is a six-carbon sugar, so it is a hexose. Ribose is a pentose, while glyceraldehyde and erythrose are trioses/tetroses.
Glucose is a six-carbon sugar, so it is a hexose. Ribose is a pentose, while glyceraldehyde and erythrose are trioses/tetroses.
Which of the following statements about lipids is correct?
- A. They are always polymers made of repeating monomers
- B. They are soluble in water and insoluble in organic solvents
- C. They are generally insoluble in water but soluble in non-polar solvents
- D. They always contain nitrogen
Answer: C. They are generally insoluble in water but soluble in non-polar solvents
Lipids are hydrophobic molecules, so they do not dissolve in water but dissolve in non-polar solvents like ether or chloroform. They are not true polymers in the usual sense.
Lipids are hydrophobic molecules, so they do not dissolve in water but dissolve in non-polar solvents like ether or chloroform. They are not true polymers in the usual sense.
Which of the following statements about enzymes is correct?
- A. All enzymes are proteins and require no cofactors
- B. Enzymes decrease activation energy and are highly specific
- C. Enzymes are consumed during the reaction
- D. Enzymes change the equilibrium of the reaction permanently
Answer: B. Enzymes decrease activation energy and are highly specific
Enzymes act as biological catalysts by lowering activation energy and showing substrate specificity. They are not consumed and do not permanently change reaction equilibrium.
Enzymes act as biological catalysts by lowering activation energy and showing substrate specificity. They are not consumed and do not permanently change reaction equilibrium.