Unit 1 Chapter 3: Enzymes — Online MCQ Test
BOTANY · CLASS 12 INTERMEDIATE 2 YEAR · Telangana State Board
Practice Unit 1 Chapter 3: Enzymes with a free chapter-wise online MCQ test.
This chapter covers: This chapter covers enzyme structure nomenclature chemical nature mechanism of enzyme action enzyme kinetics factors affecting enzyme activity and enzyme classification systems..
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Unit 1 Chapter 3: Enzymes — Important Questions & Answers
What are enzymes mainly made of in living organisms?
- A. Carbohydrates
- B. Proteins
- C. Lipids
- D. Nucleic acids
Answer: B. Proteins
Most enzymes are proteins, though a few RNA molecules can also act as catalysts. In school-level biology, enzymes are mainly described as proteinaceous in nature.
Most enzymes are proteins, though a few RNA molecules can also act as catalysts. In school-level biology, enzymes are mainly described as proteinaceous in nature.
The term used for naming an enzyme that acts on sucrose is:
- A. Maltase
- B. Sucrase
- C. Amylase
- D. Lipase
Answer: B. Sucrase
Sucrase is the enzyme that catalyzes the breakdown of sucrose. Enzymes are often named after the substrate or the reaction they catalyze.
Sucrase is the enzyme that catalyzes the breakdown of sucrose. Enzymes are often named after the substrate or the reaction they catalyze.
Enzymes lower the activation energy of a reaction by:
- A. Increasing the energy of reactants
- B. Providing an alternative reaction pathway
- C. Converting products back into substrates
- D. Increasing the temperature permanently
Answer: B. Providing an alternative reaction pathway
Enzymes speed up reactions by offering an alternative pathway with lower activation energy. They do not get consumed during the reaction.
Enzymes speed up reactions by offering an alternative pathway with lower activation energy. They do not get consumed during the reaction.
Which enzyme class catalyzes the transfer of a functional group from one molecule to another?
- A. Ligases
- B. Transferases
- C. Isomerases
- D. Lyases
Answer: B. Transferases
Transferases catalyze the transfer of functional groups such as amino, methyl, or phosphate groups. This is one of the major enzyme classes in the IUB system.
Transferases catalyze the transfer of functional groups such as amino, methyl, or phosphate groups. This is one of the major enzyme classes in the IUB system.
Which of the following statements about enzyme nomenclature is correct?
- A. All enzyme names must end with the suffix -ase, without exception
- B. Enzymes may be named based on substrate, reaction type, or common name
- C. Only the IUB system uses substrate-based naming
- D. Enzyme names never reflect the reaction they catalyze
Answer: B. Enzymes may be named based on substrate, reaction type, or common name
Enzymes can be named by substrate, by the reaction they catalyze, or by common/traditional names. The IUB system provides a systematic classification with EC numbers.
Enzymes can be named by substrate, by the reaction they catalyze, or by common/traditional names. The IUB system provides a systematic classification with EC numbers.