BUTEREGIRLS'NATIONALSCHOOL
MOCK EXAMS 2025
Kenya Certificate of Secondary Education
NAME________________________________ ADM NO___________ CLASS__________
231/3
BIOLOGY
PAPER 3
TIME: 1 ¾ HOURS
Biology
Practical
INSTRUCTIONS TO CANDIDATES:
Write your name and admission number in the spaces provided.
Sign and write date of examination in the spaces provided above
Answer all the questions in section A and B
For Examiner’s Use Only:
You are required to spend the first 15 minutes of the 1 ¾ hours allowed for this paper reading the whole
paper carefully.
QUESTIONS MAXIMUM SCORE CANDIDATE’S SCORE
TOTAL 40
1. You are provided with solution V and substance K,
2M hydrochloric acid,
Thermometer,
White tile
Dropper,
Measuring cylinder
Three labels
Six test tubes
a) Place a drop of solution V onto a white tile, add a drop of iodine solution and record your
observation (1mark)
…………………………………………………………………………………………………………
b) Add 2ml of solution V in a test tube add equal amount of benedicts solution and heat record your
observation (1mark)
…………………………………………………………………………………………………………
c) Label three test tube as A,B and C. add 2ml of substance K in each of the labeled test tube,
- In test tube A add 1ml of solution V, and place it in a water bath maintained at 370c for 25
minutes.
- In test tube B add 1ml of water and heat to boil for two minutes, allow it to cool for 1minute and
add solution V Place it in a water bath maintained at 370 c for 25minutes.
- In test tube C add 1ml 2M hydrochloric acid and shake allow it to stand for 1minute, and add
solution and place it in a water bath maintained at 370c for 25 minutes.
d) Cool the content in the test tube A, B and C by dipping in cold water in a beaker.
e) Place 2ml of the content of A in a test tube and add equal amount of Benedicts’ solution and record
your observation in the table below. repeat the procedure using the content in test tube B and C
(3marks)
Test tube
A
Test tube
B
Test tube
C
f) Account for your observation in the :-
Test tube A (2marks)
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Test tube B (2marks)
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Test tube C (2marks)
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g) Name the likely identity of substance K (1mark)
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h) What happens to the product in test tube A in the body of an organism (2marks)
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2. Below are photographs of seedlings G and X
a) The two plants belong to the same class. with reason identify the class using observable features
(2marks)
Class
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Reason
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………………………………………………………………………………………………………
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b) With a reason name the type of germination (4marks)
Type of germination in G
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Reason
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Type of germination in X
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Reason
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c) Give three functions of part labeled B. (3marks)
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d) Explain how the part labeled A straightens (3marks)
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e) Name the type of root system that develops in seedling G (1mark)
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3. Use the photographs below and specimen M provided.
a) Identify bone :- (3marks)
M
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R
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F
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b) Name the type of skeleton formed by the above bones and specimen M (1mark)
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c) Name the type of joint formed at point H (1mark)
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d) Name the fluid found at point H and state it function (2marks)
Fluid
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Function
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e) Give two adaptation of bone F to the formation of joint. (2 marks)
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f) Name the substance that harden bones (1mark)
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g) Which type of connective tissue helps to stabilize the ankle joint during the movements? (1mark)
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h) Name the blood cells produced and the section on the bone that produces these blood cells
(2marks)
Blood cell
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Section of the bone
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i) Name the condition shown by the photograph below (1mark)
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