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Paper 3

1. You are provided with specimen labeled M-soaked millet.

Grind them using pestle and mortar, adding some water to get fine solution. Label four clean test

tubes: A,B,C, and D. Put about 4ml of the solution into each of the four test tubes.

a) To solution in test tube A, add some few drops of iodine. Shake the solution to mix well.

Pour some little solution onto a white tile.

(i) Note down your observations. 1mk*Kyo*

(ii) Account for your observations in a) (i) above 1mk*Kyo*

b) Into solutions in test tube B, add about 2ml of Benedict’s solution. Place it in a boiling water

bath.

(i) After about 3 minutes, record your observations 1mk*Kyo*

(ii) What is your conclusion from observation in b) i) above. 1mk*Kyo*

c) For the remaining test tubes:-

- To test tube C, add about 3ml of solution labeled K.

- To test tube D, add about 3ml of solution K and about 2ml of solution labeled L

- Place both mixtures C and D in a water bath. Maintain the water bath at 37 0

C

- Allow it to stand in the water bath for 30 minutes.

After 30 minutes, remove the test tubes. Add about 2ml of Benedicts solution to each test tube

and shake well. Place the two test tubes in a boiling water bath. After about 5 minutes record

your observations in the table below 3mks*Kyo*

Test tube Observations Deductions

C

D

d) Account for your observations in the test tubes C and D. 2mks*Kyo*

e) i) Why was set up placed at 370C? 1mk*Kyo*

(ii) Suggest identity of solutions:- 2mks*Kyo*

2. The figure below is a photo micrograph part of a cell. Study it carefully and answer the questions

that follow.

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2

a) Name the cell organelles labeled:- M ,N , P , Q , & R

5mks*Kyo*

b) i) State the function of the part labeled P & Q 2mks*Kyo*

iii) State one adaptation of structure P to its functions. 2mks*Kyo*

c) The magnification of this photomicrograph is x 30,000. Measure the length of cell orgalle P in

mm ………………………………………

Calculate the actual length of the cell organelle P in micrometres ( µm) before the magnification.

4mks*Kyo*

3. You are provided with specimen labeled J.

a) (i) Suggest the agent of pollination for this specimen. 1mk*Kyo*

(ii) Give a reason for your answer. 1mk*Kyo*

b) Classify the specimen into:- 2mks*Kyo*

(i) Division –

Reason –

(ii) Class- 2mks*Kyo*

Reason –

c) Carefully cut the specimen J longitudinally to get two identical halves. Draw and label one

half of the flower. State the magnification. 5mks*Kyo*

d) Give one advantage and one disadvantage of sexual reproduction in plants.

(i) Advantage 1 mk*Kyo*

(ii) Disadvantage 1mk *Kyo*