The diagrams below are illustrations of an experiment to demonstrate a biological principle.

Study the diagram carefully and answer the questions that follow.

1. Name the parts labelled I and II.

2. State two differences between the set-ups A and B.

3. What is the role played by the part labelled I in the experiment?

4. Name the biological principle being demonstrated in this experiment.

5. State one way in which plants benefit from the principle named in (iv).

6. State one way in which animals benefit from the principle named in (iv).

In an experiment to investigate the reactivity of zinc, a piece of the metal was dropped into a test tube containing dilute hydrochloric acid. The experiment set-up is illustrated below.

Study the set-up carefully and answer the questions that follow.

1. Write a balanced chemical equation for the reaction that occurred in the experiment.

2. Name the gas evolved.

3. List two metals which can react in a similar way as the zinc.

4. List two metals which cannot react in a similar way as the zinc.

5. Name two glass apparatus which could have been used instead of the test tube.

The diagram below is an illustration of a thermos flask.

Study the diagram carefully and answer the questions that follow.

1. Name the parts labelled I, II, III, IV and V.

2. How does the device minimize heat loss or gain through

   (α) conduction?

   (β) convection?

   (γ) radiation?

3. State one use of the thermos flask.

The diagrams below illustrate an experimental set-up on a physical property of soil using three soil types X, Y and Z.

Study the set-up carefully and answer the questions that follow:

1. Name the parts of the set-up labelled I, II, III and IV.

2. Which of the three soil types has the

   (α) highest water holding capacity?

   (β) least water holding capacity?

3. Name each of the three soil types X, Y and Z.

4. Suggest a suitable title for the experiment.