9th Class Biology Second half Book Paper

Q1. Multiple choice questions (Attempt all · 12 × 1 = 12)

1. Which of the following processes if used by plants to make oxygen during the process of photosynthesis?

   1. Intake of water

   2. Intake of CO₂

   3. Photolysis of water

   4. Calvin cycle

2.  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

3. Female reproductive part of a flower is called:

   1. Androecium

   2. Gynoecium

   3. Calyx

   4. Corolla

4. Sucrose enters the sieve tubes of phloem by ......:

   1.  Passive transport 

   2. Osmosis 

   3. Diffusion 

   4. Active transport

5. lf is the value 155+160/2, then median of this value is:

   1. 157.5

   2. 157.6

   3. 157.7

   4. 157.9

6. Light reactions of photosynthesis occur in;

   1. Plasma membrane of cell

   2. Cytoplasm of cell

   3. Stroma of chloroplasts

   4. Thylakoids of chloroplasts

7. 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

8. Strawberry reproduce by using its:

   1. Bulbs 

   2. Stolon

   3. Tuber 

   4. Rhizome 

9. The transpiration is regulated by:

   1. Mesophyll

   2. Guard cells

   3. Xylem

   4. Phloem

10. Which use of biostatistics help in planning vaccination campaigns:

    1. Predicting outcomes

    2. Public health 

    3. Policy making

    4. None

11. Which molecule donates electrons in the light-dependent reactions of photosynthesis?

    1. NADPH

    2. Water

    3. Oxygen

    4. Carbon dioxide

12. 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