9th Class Biology Chapter 7 TestEnzymes

Q1. Multiple choice questions (Attempt all · 10 × 1 = 10)

1.  What happens when the pH changes for an enzyme?

   1. It increases the enzyme's activity

   2.  It alters the ionization of amino acids at the active site, slowing or blocking enzyme activity

   3. It strengthens the enzyme's bond with the substrate

   4. It increases the enzyme's temperature

2. What are enzymes?

   1.  Chemical catalysts that are consumed during reactions

   2.  Biological catalysts that accelerate chemical reactions without being consumed

   3. Substances that slow down chemical reactions

   4. Non-protein molecules that catalyze reactions

3. Ionization of amino acids at the active site is affected by?

   1. Change in temperature

   2. Change in substrate concentration

   3. Change in pH

   4. Change in temperature and substrate concentration

4. What is metabolism?

   1. The breakdown of glucose into energy

   2.  The sum of all chemical reactions that occur within an organism to sustain life

   3.  The conversion of carbon dioxide into glucose

   4. The process of forming proteins from amino acids

5. Photosynthesis is the process of:

   1. Breaking down glucose into energy

   2.  Converting carbon dioxide and water into glucose and oxygen using sunlight

   3. Forming proteins from amino acids

   4. Oxidizing food into carbon dioxide and water

6. Enzymes are specific in their action because:

   1. Their active sites fit specific substrates

   2. They are always proteins

   3. They are consumed in reactions

   4. They work only at high temperatures

7. An example of a non-competitive inhibition is:

   1. Antibiotics

   2. Mercury

   3. Toxic substances

   4. Poison

8. What happens to the substrate after the enzyme catalyzes the reaction?

   1. It remains unchanged and is stored in the active site

   2.  It transforms into products, which are released

   3.  It breaks the enzyme apart

   4. It permanently binds to the enzyme

9. Which does yield energy?

   1. Anabolism

   2. Catabolism

   3. Metabolism

   4. None

10. Set of biochemical reactions that occur in living organisms in order to maintain life is called?

    1. Catabolism

    2. Anabolism

    3. Metabolism

    4. Mutualism