TRIAL 6
FORM THREE
BIOLOGY PAPER 3
CONFIDENTIAL
- Each candidate should have the following
- Liquid cooking oil (about 20ml)
- B1 – conc. Sodium hydrogen carbonate solution in a beaker
- B2 – 1% starch solution
- Irish potato
- At least six (6) test tubes
- Means of heating
- Benedict’s solution
- Scapel
- Pestle and mortar
_________________________________________
Name……………………………………………………… Index Number……………………………..
Date……………………………………….. Candidates signature…………………….
231/2
BIOLOGY
PAPER 2
(THEORY)
FORM 3
TIME: 2 HOURS
Instructions to the Candidate
- Write your name, index number, sign and date of the examination.
- Answer all questions in section A and in Section B question 6 and any other one.
- Non-programmable electronic calculators may be used.
- ALL working must be clearly shown where necessary.
For Examiner’s Use Only
Questions | Maximum Score | Candidate’s Score |
1 | 8 | |
2 | 8 | |
3 | 8 | |
4 | 7 | |
5 | 9 | |
6 | 20 | |
7 | 20 | |
8 | 20 | |
Grand Total | 80 |
Also read..
BIOLOGY FORM ONE SUMMARIZED NOTES
Biology Form one to four exams, notes and revision materials
BIOLOGY FORM FOUR SUMMARIZED NOTES
BIOLOGY FORM TWO SUMMARIZED NOTES
Biology notes form 1-4; Free KCSE downloads
BIOLOGY FORM THREE SUMMARIZED NOTES
Biology notes (Updated form one to four free notes)
Biology Simplified Notes Form 1 to 4 Free
Biology Free notes and Exams for Form one to Four
BIOLOGY KCSE MARKING AND SETTING TIPS IN LINE WITH EMERGING TRENDS
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Biology KCSE Past Papers and all marking schemes free downloads
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Syllabus For All Secondary Schools Per Subjects (Latest Syllabus)
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FORM 4 EXAMINATIONS AND MARKING SCHEMES: ALL SUBJECTS FOR KCSE CANDIDATES- OVER 1,000 PAPERS
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FORM 3 ALL SUBJECTS EXAMS, ASSIGNMENTS: FREE TERM 1-3 EXAMS & ANSWERS
Updated Secondary School Notes form one to four Free Downloads (All subjects Comprehensive Notes)
Physics free lesson plans for all topics (Form one to four)
SECTION A.
Answer all questions in this section.
- Examine the diagram below and use it to answer the questions that follow.
(a) Name the parts labeled B, C and D. (3marks)
……………………………………………..……………………………………………………………………
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(b) What substance makes up part labeled A? (1mark)
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(c) Name the process by which mineral salts move into structure B. (1mark)
……………………………………………..……………………………………………………………………
(d) Explain what happens when a red blood cell is put in distilled water. (3marks)
……………………………………………..……………………………………………………………………
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- In an experiment, equal volume of blood were incubated for one hour with different salt concentration. After incubation the number of red blood cells in each set up was determined. The result are as shown in the table below.
(a) Account for the result in set up A. (2marks)
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
(b) In what way would you expect the cells in set up B to differ from those in set up A? (2 marks)
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
(c) What observation would you expect to make with regard to the number of red blood cells if the experiment was repeated with a salt solution of 1.4 % (1mark)
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
(d) What process lead to the observations made in B and C. (1mark)
……………………………………………..……………………………………………………………………
(e) State two roles of the process mentioned in d above in plants. (2marks)
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
- The diagram below represents a simplified nitrogen cycle. Study it and answer the questions that follow.
Ammonia |
Plant proteins |
Nitrogen in air |
Z
W Denitrifying Bacteria
Compound Y |
Nitrites |
X
(a) Name the organisms represented by W and Z. (2marks)
……………………………………………..……………………………………………………………………
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(b) Name the process X (1mark)
……………………………………………..……………………………………………………………………
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(c) Describe the role of lightning in nitrogen fixation. (3marks)
……………………………………………..……………………………………………………………………
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(d) Explain why process W is important to ecosystems. (1mark)
……………………………………………..……………………………………………………………………
(e) What is the role of nitrogen as an element in living organisms? (1mark)
……………………………………………..……………………………………………………………………
- The diagram below represents part of a gaseous system in a grasshopper.
P Q
(a) Name the structures labeled P and Q (1mark)
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
(b) State the function of the structure labeled P (1mark)
……………………………………………..……………………………………………………………………
(c) Describe the path taken by carbon (IV) oxide from the tissues of the insect to the
atmosphere (3marks)
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
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(d) How is the structure labeled Q adapted to its functions (2marks)
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- The set up below illustrates an experiment to demonstrate a certain biological process, before the addition of the yeast suspension the glucose solution was first boiled and then cooled at 40o
(a) What was the aim of the experiment? (1mark)
……………………………………………..……………………………………………………………………
(b) What observations would you make in the tubes a few minutes after the experiment begun?
(2marks)
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
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(c) Explain the observations made in (b) above (2marks)
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(d) Why was glucose solution boiled before cooling at 40oC (1mark)
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(e) How can you set up a control experiment for the above (1mark)
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(f) Give two importance of the above processes (2marks)
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……………………………………………..……………………………………………………………………
SECTION B
Answer question6 (compulsory)and either question 7 or 8in the spaces provided after question
- An experiment was carried out to investigate heat production in J/r and heat loss in J/hr in a man at different environmental temperature (ºC). Heat production and heat loss were determined as air temperature changed. The results were shown in the table below.
(a) Using the same axes, draw graphs of heat production and heat lost in j/hr against air
temperature in ºC. (7marks)
(b) At what air temperature does the body lose as much heat as it produces? (1mark)
……………………………………………..……………………………………………………………………
(c) (i) Explain the relationship between heat loss and heat production at 40ºC (3marks)
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(ii) Explain why readings for this experiment were not taken for air temperatures above 40ºC (2marks)
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(d) (i) Explain how sweating helps the body to lose excess heat. (2marks)
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(ii) State three ways in which mammals are adapted to live in regions below sub-zero
temperatures. (3marks)
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(e) Explain the role of hypothalamus in temperature regulation. (2marks)
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- Describe the functions of the parts of a mammalian skin. (20marks)
- Describe how water moves from the soil to the leaves in a tree until evaporation occurs. (20marks)
___________________________________________
Name………………………………………………………. Index Number………….……………………..
Date……………………………………….. Candidates signature…………………….
231/1
BIOLOGY
PAPER 1
(THEORY)
FORM 3
2 HOURS
Instructions to the Candidate
- Write your name, index number, sign and date of the examination.
- Answer ALL questions in the spaces provided.
- Non-programmable electronic calculators may be used.
- ALL working must be clearly shown where necessary.
FOR EXAMINER’S USE ONLY
QUESTION | MAXIMUM SCORE | CANDIDATE’S SCORE |
1 – 31 |
80 |
Answer all questions.
- Define the following terms. (2 marks)
(a) Parasitology
…………………………………………..……………………………………………………………………… (b) Entomology
…………………………………………..………………………………………………………………………
- Explain what happens during the dark stage of photosynthesis. (3 marks)
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- The diagram below shows a species of a plant. Study it carefully and answer the questions to follow.
(a) State the class to which the above specimen belongs (1mark)
…………………………………………..………………………………………………………………………
(b)Reason (1mark)
…………………………………………..………………………………………………………………………
- What is the significance of the following?
(a) Cartilage in the trachea (1mark)
…………………………………………..………………………………………………………………………
(b) Mucus on the inner surface of the trachea. (1mark)
…………………………………………..………………………………………………………………………
(c) Moisture on the surface of the alveoli (1 mark)
…………………………………………..………………………………………………………………………
- State three properties of the cell membrane. (3 marks)
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- What is meant by the following terms?
(a) Protandry (1mark)
…………………………………………..………………………………………………………………………
(b) Self-sterility (1mark)
…………………………………………..………………………………………………………………………
- State the importance of each of the following excretory products in plants.
(a) Rubber (1 mark)
…………………………………………..………………………………………………………………………
(b) Papain (1 mark)
…………………………………………..………………………………………………………………………
- The set up below was prepared by a form one student study it and answer the questions that follow.
- After a few hours it was found that reducing sugars were present in the distilled water. State what happened.
(i) Inside the tube shaped membrane (1mark)
…………………………………………..………………………………………………………………………
…………………………………………..………………………………………………………………………
(ii) At the walls of the membrane (1mark)
…………………………………………..………………………………………………………………………
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- The apparatus above is a poor representation of the ileum. Give two reasons to support this statement. (2marks)
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- Distinguish between natural and acquired immunity. (2marks)
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- (a) Define the following terms (2 marks)
(i) Carrying capacity
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(ii) Synecology
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(b) Distinguish between population and community (2 marks)
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- (a) State the class to which organism shown in the diagram below belongs. (1mark)
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(b) Give three characteristics used to place the organism into the class named in (a) above.
(3marks)
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- The diagram below was set up to study a certain physiological process. Glucose solution was boiled and cooled before adding yeast.
(a) Identify the process being investigated. (1mark)
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(b) What observation was made after 8 hours? (1mark)
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(c) State and explain the expected results if the yeast suspension was boiled and then put in
glucose solution? (2 marks)
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- State two ways in which the root hairs are adapted to their functions. (2marks)
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- Define the following terms. (2marks)
(a) Excretion
…………………………………………..………………………………………………………………………
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(b) Secretion
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- Study the figure below and answer the questions that follow.
(a) Name the parts labeled B, C and D (3marks)
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(b) State the function of part labeled A. (1mark)
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- What is meant by the term binomial nomenclature (1mark)
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- State two characteristics of aerenchyma tissue. (2marks)
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- Explain what happens when there is oxygen debt in human muscles. (2marks)
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- State the adaptations of the following tissues for support in plants. (2marks)
(a) Collenchyma
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(b) Sclerenchyma
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- Study the fruits below and classify them, giving reasons.
Seeds |
Pericarp |
- Type of fruit (1mark)
…………………………………………..……………………………………………………………………… Reason (1mark)
…………………………………………..……………………………………………………………………
Remains of the style |
Attachment to cob |
- Type of fruit (1mark)
…………………………………………..………………………………………………………………………
Reason (1mark)
…………………………………………..………………………………………………………………………
- During which phase of meiosis does crossing occurs. (1mark)
…………………………………………..………………………………………………………………………
- Give the function of the following parts of a microscope.
(a) Condenser (1mark)
…………………………………………..………………………………………………………………………
(b) State the importance of the following when preparing temporary slides. (2marks)
(i) Making a thin plant section
…………………………………………..………………………………………………………………………
(ii) Adding a drop of water
…………………………………………..………………………………………………………………………
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- Explain the importance of respiratory surface being
(a) Thin walled (1 mark)
…………………………………………..………………………………………………………………………
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(b) Moist (1 mark)
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- Explain how hair in human beings keeps the body warm (2marks)
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- The equation below represents a process that occurs in the plants.
C6H12O6 B + C2H5OH+ Energy
(a) Name the process. (1mark)
…………………………………………..………………………………………………………………………
(b) Name product B (1mark)
…………………………………………..………………………………………………………………………
(c) State the economic importance of this process. (2marks)
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- Name the spore-producing structures in
(a) Pteridophyta. (1mark)
…………………………………………..………………………………………………………………………
(b) Bryophta (1mark)
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- Give two advantages of being a homoiotherm. (2marks)
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- State how xylem vessel is adapted to its function. (3marks)
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- State functional differences between arteries and veins. (2marks)
Arteries | Veins |
|
|
|
|
- Name the hard outer covering of the members of the phylumArthropoda. (1mark)
…………………………………………..………………………………………………………………………
- State three roles played by the structure named in (a) above. (3 marks)
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_____________________________________
Name ………………………………………………… Candidate’s signature ………………
Date …………………………………………………..
231/2
Biology
Time: 2hrs.
Term 3
Biology
Paper 231/2
Time: 2 hrs
Instructions to candidates
- Write your name, index number in the spaces provided above.
- Sign and write the date of examination in the spaces provided above.
- This paper consists of two sections A and B.
- Answer all the questions in section A in the spaces provided.
- In section B answer question 6 (compulsory) and either question 7 or 8 in the spaces provided after question 9.
- Check to ascertain that all pages are printed and that no questions are missing.
FOR EXAMINER’S USE ONLY
SECTION | QUESTIONS | MAXIMUM SCORE | CANDIDATES SCORE |
1
|
8 | ||
2
|
8 | ||
3
|
8 | ||
4
|
8 | ||
5
|
8 | ||
6
|
20 | ||
7
|
20 | ||
8
|
20 | ||
|
|||
Total score |
|
80 |
SECTION A 40 MARKS
Answer all questions in this section in the spaces provided
Q1. The food web represents a feeding relationship in an ecosystem.
Hawk
- Name two organisms which are both secondary and tertiary consumers (2mks)
- State the short term effect of immigration of insects in the ecosystem. (2mks)
- Which organism has the least biomass in the food web? Give reasons (2mks)
- Explain the disadvantages of using synthetic pesticides over biological control in agriculture (2mk)
Q2. The diagram shows a white blood cell
- Describe how the bacteria entered into the cell (2mks).
- What happens to the bacteria once in the cell? (2mks)
- (i) Name the kingdom whose members exhibit the same process that leads to entry of bacteria in the cell (1mk)
(ii) besides the process described in (a) above, state two ways by which white blood cells protect the body. (2mks).
(iii) State where white blood cells (lymphocytes) are made. (1mk)
Q3. A group of students set up an experiment to investigate a certain physiological process. The set up is as shown in the diagram below:
- After sometime, the students observed that the level of the sugar solution had risen. What physiological process was being investigated? (1mk)
- Account for the rise in the level of sugar solution in the experiment. (3mks)
- (i) Suggest the results that the students would obtain if they repeated the experiment
Using a piece of boiled paw paw. ( 3mks)
(ii) Give a reason for your answer in (c) (i) above (1mk)
Q4. The graph shows relationship between body size and surface area to volume ratio of
Organisms. Three animal species A, B and C are marked on the graph.
- Which of the three animals is likely to have the simplest transport system? Give a reason for your answer (2mks).
- Give the formula used to calculate surface area to volume ratio of an organism. (1mk).
- State two disadvantages of small surface area to volume ratio in organisms. (2mks).
- Showing your working, calculate the surface area to volume ratio of the following organisms X and Y.
Q5. The diagram represents a plant cell.
- Name a carbohydrate which forms the structure labeled S (1mk)
- (i) State the function of the part labeled R (2mks)
- Name two cell organelles present in the diagram but absent in animal cells (2mks)
- Complete the following table.
Eye – piece lens magnification | Objective lens magnification | Total magnification |
X10 | X5 | |
X40 | X600 |
(2mks)
SECTION B (40 MARKS)
Answer question 6 (compulsory) and either question 7or 8 in the spaces provided after question 8.
Q6. The results below were obtained in a class experiment to investigate how water loss varies
Throughout the day in tropical plants.
Time in day (hrs) | 2.00am | 6.00am | 8.00am | 10.00am | 12.00am | 1.00pm | 2.00pm | 3.00pm | 4.00pm | 6.00pm | 8.00pm | 12.00 midnight |
Water loss
gm-2 h -1 |
14 | 35 | 135 | 275 | 315 | 285 | 245 | 175 | 75 | 16 | 16 |
- ) Plot a graph of amount of water lost against time. (6mks)
(ii) At what time of the day was 210 mg-2h-1 of water lost? (1mks)
- Account for the amount of water lost between
(i) 2.00 a.m and 6.00 a.m (2mks)
(ii) 6.00 a.m and 1.00 p.m (2mks)
(ii) 1.00 p.m and 6.00 p.m (2mks)
- (i) Which set of apparatus was used in the experiment? (1mks)
(ii) State the effect of putting an electric fan near the apparatus during the experiment. Give a reason for your answer (2mks)
- In a related ecological study two habitats each of 25 meters square were studied for five hours. Habitat A was an open pond while B was a forested area. More water was found to be lost in habitat B than A. explain (2 mks)
- In a related ecological study two habitats each of 25 meters square were studied for five hours. Habitat A was an open pond while B was a forested area. More water was found to be lost in habitat B than A. explain (2 mks)
- (a) Giving examples,describe how various fruits and seeds are suited to different methods
dispersal. (17mks)
(b) state the differences between a seed and a fruit.(3mks)
- Describe how the ileum is adapted to its functions. (20mks)
______________________________________
FORM 3 PRACTICAL
BIOLOGY QUESTIONS
- a) You are provided with a food substance labeled T and reagents in the wash bottles. Use them to carry out respective food tests and record your procedure used, observations and your conclusion in the table below. (16mks)
Test | Procedure | Observation | Conclusion |
- b) How does the food tested above used in the body of animal. (1mk)
- a) leaf simple ………………………………go to 2
- b) leaf compound …………………………… go to 5
2.a) Leaf parallel veined …………………………..zea
- b) leaf net –veined ……………………………….. go to 3
3.a) leaf apex lobed ………………………………. Aleurites
- b) leaf apex pointed …………………………….go to 4
4.a) leaf margin smooth ……………………………. Achyranthes
- b) _______________ ………………………………hibiscus
5.a)leaf palmately compound ………………………… go to 6
- b) leaf pinnately compound ………………………….. go to 7
6.a) leaf trifoliately compound ………………………….oxalis
- b) leaf with more than three leaflets ……………………….chorisia
7.a) leaf unipinnately compound …………………………… cassia
- b) _________________ ……………………………………….go to 8
- a) has terminal leaflets ……………………………………..jacaranda
- b) __________________ …………………………………. Acacia
- b) Use the dichotomous key to identify each of the plant specimens in the photographs to their genus. In each case given the sequence of steps followed (18mks)
Specimen | Steps | Identify |
K1 | ||
K2 | ||
K3 | ||
K4 | ||
K5 | ||
K6 | ||
K7 | ||
K8 | ||
K9 |
- c) State the difference in the apex of the leaflet of K1 and leaf K2 (2mks)
________________________________________________________
Name……………………………………………………… Index Number……………………………..
Date……………………………………….. Candidates signature…………………….
231/2
BIOLOGY
PAPER 2
(THEORY)
FORM 3
TIME: 2 HOURS
Instructions to the Candidate
- Write your name, index number, sign and date of the examination.
- Answer all questions in section A and in Section B question 6 and any other one.
- Non-programmable electronic calculators may be used.
- ALL working must be clearly shown where necessary.
For Examiner’s Use Only
Questions | Maximum Score | Candidate’s Score |
1 | 8 | |
2 | 8 | |
3 | 8 | |
4 | 7 | |
5 | 9 | |
6 | 20 | |
7 | 20 | |
8 | 20 | |
Grand Total | 80 |
SECTION A.
Answer all questions in this section.
- Examine the diagram below and use it to answer the questions that follow.
(a) Name the parts labeled B, C and D. (3marks)
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
(b) What substance makes up part labeled A? (1mark)
……………………………………………..……………………………………………………………………
(c) Name the process by which mineral salts move into structure B. (1mark)
……………………………………………..……………………………………………………………………
(d) Explain what happens when a red blood cell is put in distilled water. (3marks)
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
- In an experiment, equal volume of blood were incubated for one hour with different salt concentration. After incubation the number of red blood cells in each set up was determined. The result are as shown in the table below.
(a) Account for the result in set up A. (2marks)
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
(b) In what way would you expect the cells in set up B to differ from those in set up A? (2 marks)
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
(c) What observation would you expect to make with regard to the number of red blood cells if the experiment was repeated with a salt solution of 1.4 % (1mark)
……………………………………………..……………………………………………………………………
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(d) What process lead to the observations made in B and C. (1mark)
……………………………………………..……………………………………………………………………
(e) State two roles of the process mentioned in d above in plants. (2marks)
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- The diagram below represents a simplified nitrogen cycle. Study it and answer the questions that follow.
Ammonia |
Plant proteins |
Nitrogen in air |
Z
W Denitrifying Bacteria
Compound Y |
Nitrites |
X
(a) Name the organisms represented by W and Z. (2marks)
……………………………………………..……………………………………………………………………
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(b) Name the process X (1mark)
……………………………………………..……………………………………………………………………
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(c) Describe the role of lightning in nitrogen fixation. (3marks)
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(d) Explain why process W is important to ecosystems. (1mark)
……………………………………………..……………………………………………………………………
(e) What is the role of nitrogen as an element in living organisms? (1mark)
……………………………………………..……………………………………………………………………
- The diagram below represents part of a gaseous system in a grasshopper.
P Q
(a) Name the structures labeled P and Q (1mark)
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
(b) State the function of the structure labeled P (1mark)
……………………………………………..……………………………………………………………………
(c) Describe the path taken by carbon (IV) oxide from the tissues of the insect to the
atmosphere (3marks)
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
……………………………………………..……………………………………………………………………
(d) How is the structure labeled Q adapted to its functions (2marks)
……………………………………………..……………………………………………………………………
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- The set up below illustrates an experiment to demonstrate a certain biological process, before the addition of the yeast suspension the glucose solution was first boiled and then cooled at 40o
(a) What was the aim of the experiment? (1mark)
……………………………………………..……………………………………………………………………
(b) What observations would you make in the tubes a few minutes after the experiment begun?
(2marks)
……………………………………………..……………………………………………………………………
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(c) Explain the observations made in (b) above (2marks)
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(d) Why was glucose solution boiled before cooling at 40oC (1mark)
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(e) How can you set up a control experiment for the above (1mark)
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(f) Give two importance of the above processes (2marks)
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SECTION B
Answer question6 (compulsory)and either question 7 or 8in the spaces provided after question
- An experiment was carried out to investigate heat production in J/r and heat loss in J/hr in a man at different environmental temperature (ºC). Heat production and heat loss were determined as air temperature changed. The results were shown in the table below.
(a) Using the same axes, draw graphs of heat production and heat lost in j/hr against air
temperature in ºC. (7marks)
(b) At what air temperature does the body lose as much heat as it produces? (1mark)
……………………………………………..……………………………………………………………………
(c) (i) Explain the relationship between heat loss and heat production at 40ºC (3marks)
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(ii) Explain why readings for this experiment were not taken for air temperatures above 40ºC (2marks)
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(d) (i) Explain how sweating helps the body to lose excess heat. (2marks)
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(ii) State three ways in which mammals are adapted to live in regions below sub-zero
temperatures. (3marks)
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(e) Explain the role of hypothalamus in temperature regulation. (2marks)
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- Describe the functions of the parts of a mammalian skin. (20marks)
- Describe how water moves from the soil to the leaves in a tree until evaporation occurs. (20marks)
______________________________________
Name………………………………………………………. Index Number………….……………………..
Date……………………………………….. Candidates signature…………………….
231/1
BIOLOGY
PAPER 1
(THEORY)
FORM 3
2 HOURS
Instructions to the Candidate
- Write your name, index number, sign and date of the examination.
- Answer ALL questions in the spaces provided.
- Non-programmable electronic calculators may be used.
- ALL working must be clearly shown where necessary.
FOR EXAMINER’S USE ONLY
QUESTION | MAXIMUM SCORE | CANDIDATE’S SCORE |
1 – 31 |
80 |
Answer all questions.
- Define the following terms. (2 marks)
(a) Parasitology
…………………………………………..……………………………………………………………………… (b) Entomology
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- Explain what happens during the dark stage of photosynthesis. (3 marks)
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- The diagram below shows a species of a plant. Study it carefully and answer the questions to follow.
(a) State the class to which the above specimen belongs (1mark)
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(b)Reason (1mark)
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- What is the significance of the following?
(a) Cartilage in the trachea (1mark)
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(b) Mucus on the inner surface of the trachea. (1mark)
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(c) Moisture on the surface of the alveoli (1 mark)
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- State three properties of the cell membrane. (3 marks)
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- What is meant by the following terms?
(a) Protandry (1mark)
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(b) Self-sterility (1mark)
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- State the importance of each of the following excretory products in plants.
(a) Rubber (1 mark)
…………………………………………..………………………………………………………………………
(b) Papain (1 mark)
…………………………………………..………………………………………………………………………
- The set up below was prepared by a form one student study it and answer the questions that follow.
- After a few hours it was found that reducing sugars were present in the distilled water. State what happened.
(i) Inside the tube shaped membrane (1mark)
…………………………………………..………………………………………………………………………
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(ii) At the walls of the membrane (1mark)
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- The apparatus above is a poor representation of the ileum. Give two reasons to support this statement. (2marks)
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- Distinguish between natural and acquired immunity. (2marks)
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- (a) Define the following terms (2 marks)
(i) Carrying capacity
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(ii) Synecology
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(b) Distinguish between population and community (2 marks)
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- (a) State the class to which organism shown in the diagram below belongs. (1mark)
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(b) Give three characteristics used to place the organism into the class named in (a) above.
(3marks)
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- The diagram below was set up to study a certain physiological process. Glucose solution was boiled and cooled before adding yeast.
(a) Identify the process being investigated. (1mark)
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(b) What observation was made after 8 hours? (1mark)
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(c) State and explain the expected results if the yeast suspension was boiled and then put in
glucose solution? (2 marks)
…………………………………………..………………………………………………………………………
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- State two ways in which the root hairs are adapted to their functions. (2marks)
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- Define the following terms. (2marks)
(a) Excretion
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(b) Secretion
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- Study the figure below and answer the questions that follow.
(a) Name the parts labeled B, C and D (3marks)
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(b) State the function of part labeled A. (1mark)
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- What is meant by the term binomial nomenclature (1mark)
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- State two characteristics of aerenchyma tissue. (2marks)
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- Explain what happens when there is oxygen debt in human muscles. (2marks)
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- State the adaptations of the following tissues for support in plants. (2marks)
(a) Collenchyma
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(b) Sclerenchyma
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- Study the fruits below and classify them, giving reasons.
Seeds |
Pericarp |
- Type of fruit (1mark)
…………………………………………..……………………………………………………………………… Reason (1mark)
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Remains of the style |
Attachment to cob |
- Type of fruit (1mark)
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Reason (1mark)
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- During which phase of meiosis does crossing occurs. (1mark)
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- Give the function of the following parts of a microscope.
(a) Condenser (1mark)
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(b) State the importance of the following when preparing temporary slides. (2marks)
(i) Making a thin plant section
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(ii) Adding a drop of water
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- Explain the importance of respiratory surface being
(a) Thin walled (1 mark)
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(b) Moist (1 mark)
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- Explain how hair in human beings keeps the body warm (2marks)
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- The equation below represents a process that occurs in the plants.
C6H12O6 B + C2H5OH+ Energy
(a) Name the process. (1mark)
…………………………………………..………………………………………………………………………
(b) Name product B (1mark)
…………………………………………..………………………………………………………………………
(c) State the economic importance of this process. (2marks)
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- Name the spore-producing structures in
(a) Pteridophyta. (1mark)
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(b) Bryophta (1mark)
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- Give two advantages of being a homoiotherm. (2marks)
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- State how xylem vessel is adapted to its function. (3marks)
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- State functional differences between arteries and veins. (2marks)
Arteries | Veins |
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- Name the hard outer covering of the members of the phylumArthropoda. (1mark)
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- State three roles played by the structure named in (a) above. (3 marks)
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