9th Class Biology – Short Questions & Answers

  • Define substrate.

    Define substrate.

    A substrate is the molecule upon which an enzyme acts to catalyze a chemical reaction.

  • What is enzyme specificity?

    What is enzyme specificity?

    Enzyme specificity refers to the ability of an enzyme to catalyze a particular reaction for a specific substrate.

  • Define coenzymes.

    Define coenzymes.

    Coenzymes are small organic molecules that assist enzymes in their catalytic activity, often by transferring chemical groups.

  • How do temperature and pH affect enzyme activity?

    How do temperature and pH affect enzyme activity?

    Enzyme activity increases with temperature until a certain point, after which the enzyme may denature. Extreme pH levels can also alter the enzyme’s shape, reducing its activity.

  • What is enzyme inhibition?

    What is enzyme inhibition?

    Enzyme inhibition occurs when a molecule binds to an enzyme and reduces its activity, either competitively or non-competitively.

  • Explain the mechanism of enzyme action.

    Explain the mechanism of enzyme action.

    Enzymes speed up reactions by lowering the activation energy. The substrate binds to the enzyme’s active site, forming an enzyme-substrate complex. The enzyme catalyzes the conversion of the substrate into the product, which is then released, allowing the enzyme to repeat the process.

  • Discuss the types of enzyme inhibition.

    Discuss the types of enzyme inhibition.

    Enzyme inhibition can be: Competitive Inhibition: Involves an inhibitor that competes with the substrate for binding to the active site. Non-competitive Inhibition: The inhibitor binds to a different site on the enzyme, altering its shape and reducing its activity.

  • Discuss the factors affecting enzyme activity in detail.

    Discuss the factors affecting enzyme activity in detail.

    Factors that influence enzyme activity include: Temperature: High temperatures can denature enzymes, while lower temperatures reduce activity. pH: Each enzyme has an optimal pH range, and extreme pH levels can deactivate the enzyme. Substrate concentration: Increased substrate concentration typically increases enzyme activity, up to a saturation point. Enzyme concentration: More enzymes lead to faster reactions,…

  • What is bioenergetics?

    What is bioenergetics?

    Bioenergetics is the study of the flow and transformation of energy in living organisms. It explains how energy is produced, stored, and used for various cellular processes.

  • What is ATP?

    What is ATP?

    ATP (Adenosine Triphosphate) is the energy currency of the cell. It stores and provides energy for cellular activities like muscle contraction, protein synthesis, and cell division.