1. In an experiment to determine the percentage of air in a soil sample, the following results were obtained.
Volume of soil added to measuring cylinder = 40 cm3
Volume of water added to measuring cylinder -40cm3
Volume of soil and water after stirring =75cm3

The percentage of air in the soil was
A. 6.7
B. 5.0
C. 12.5
D. 53.3

2. A couple produced children of blood group A, B, AB and O. which of the following were the genotypes of the parents?
A. BB and BO
B. AO and BO
C. BO and AA.
D. AB and OO.

3. Which one of the following is an example of continuous variation?
A. Height of students in a class
B. Blood groups among humans.
C. Types of combs in chicken.
D. Colour of eyes in humans.

4. Figure1 shows part of the epidermis of a plant leaf.

The major difference between X and y is that X.
A. is round while y is cylindrical.
B. is pigmented while y is cylindrical.
C. is living while y is transparent
D. cannot carry out photosynthesis while y can

5. Which one of the following pairs of blood constitutes play a role in blood clotting?
A. .platelets and hormones.
B. Hormones and plasma.
C. platelets and fibrinogen
D. fibrinogen and leucocytes

6. Which one of the following occurs when a cylinder of fresh potato tuber is placed in astrong solution of sucrose and left for sometime? The cylinder
A. Absorbs the solution
B. Becomes hard
C. Absorbs water.
D. Becomes soft.

7. The importance of the lateral line in fish is to
A. Provide buoyancy.
B. Provide direction.
C. Stabilize the fish.
D. detect vibrations in the water

8. Which one of the following increase the rate of diffusion at a surface?
A. Increasing the area over which diffusion occurs.
B. Increasing the distance across which diffusion occur
C. Lowering the temperature of the medium.
D. Reducing he concentration gradient of he diffusing molecules.

9. Presence of wax in the ear may result into poor perception of sound because the
A. ossicles cannot move freely.
B. Ear drum is unable to vibrate properly.
C. Eustachian tube is unable to balance the air pressure in the ear.
D. Oval window becomes rigid.

10. Which one of the following occurs in a mammal which is in a cold environment?
A. More blood flows to the skin
B. Metabolic rate decreases
C. Vaso-constriction of the skin capillaries occurs
D. Erector pill muscles relax.

11. Which one of the following plant parts is modified for food storage in a sweet potato?
A. Jointed limbs and jointed bodies.
B. Three body parts and jointed limbs
C. Here body parts and a pair of winds
D. A pair of antennae and segmented bodies.

12. Which one of the following plant parts is modified for food storage in a sweet potato?
A. Roots
B. Stem
C. Leaves
D. Buds.

13. The agent of dispersal of the fruit in figure 2 is

 

 

A. Wind
B. Water
C. Animals
D. Self

14. Which one o f the following structures are necessary in the dispersal of seeds and fruits by water?
A. Wings
B. Tough testa
C. Hairs.
D. Dry test

15. When a seedling is fixed on a rotating clinostat and placed in a horizontal position because,
A. energy and ethanol
B. Production of axins stops.
C. auxins are uniformly distributed in the shoot.
D. auxins accumulates on the supper side of the shoot.

16. Which of the following are products of both anaerobic and anaerobic respiration?
A. energy and ethanol
B. Water and energy.
C. Water, carbon dioxide and energy.
D. Carbon dioxide and energy.

17. A Vertebrata with long neutral spine, wide neutral canal and short transverse process is
A. An atlas vertebra.
B. A thoracic vertebra.
C. A limber vertebra
D. A cervical vertebra.

18. Which one of the following organs in a mammalian body performs both endocrine and exocrine functions?
A. Salivary glands.
B. testes
C. pancreas
D. Adrenal gland

19. Which one of the following activities in humans is a conditioned reflex?
A. Sleeping
B. Blinking
C. Coughing
D. Walking

20. A somatic cell in an organism contains 24 pairs of chromosomes .the number of chromosomes in a gamete of the organisms is
A. 24
B. 12
C. 48
D. 6.

21. Glucose is not contained in the urine of a healthy person because
A. All the glucose passes back into the blood stream.
B. The glomerulus is impermeable to glucose.
C. Glucose is used for respiration before reaching the kidney.
D. The kidney converts glucose to urea.

22. Which of the following describes a community it ecology?
A. Number of organisms of a given species in an area.
B. Nutritional interrelationship of organisms.
C. Collection of species of organisms.
D. Place where organisms live.

23. Double fertilization plants refers to two male nuclei with
A. Antipodal nuclei and polar nuclei.
B. Egg nucleus polar nuclei.
C. Egg nucleus and antipodal nuclei.
D. Two egg nuclei

24. Termites are able to eat wood because
A. They produce cellulose enzyme.
B. They posse’s strong mandibles.
C. Microscopic fungi live in their guts.
D. They ingest only small pieces.

25. Which of the following is a role of bile in food digestion?
A. Providing suitable medium for action of enzymes in the duodenum.
B. breaking down fats
C. acting enzymes
D. Catalyzing the action of enzymes.

26. Which of the following characteristics of a plant leaf is important in ensuring maximum absorption of light energy?
A. Numerous stomata on lower epidermis.
B. Well spaced spongy mesophyll cells.
C. Compact palisade cells.
D. Waxy cuticle on upper epidermis.

27. The table 1 shows results obtained from an investigation carried out on a fresh water plant. The plant was placed under water which had its carbon dioxide concentration varied as the number of bubbles of oxygen evolved per minute by the plant, was observed and recorded. The experiment was carried out under sunlight at 25⁰C

Carbon dioxide concentration (percentage by volume)	Number of oxygen bubbles per minute
0.00	0
0.02	04
0.08	20
0.14	24
0.18	24

 

 

a) What was the aim of the experiment?
b) In the space provided, draw a graph to represent the information in table 1
c) Using the information ,explain he observations
(i) At carbon dioxide concentration of 0.00
(ii) Between the carbon dioxide concentration of 0.02 and0.18.
d) Suggest an explanation for what would be observed in the experiment .if the
(i) Carbon dioxide concentration was increase
(ii) Temperature was lowered to 5⁰C.
e) Giving an example in each case, explain what is meant by
(i) Exocrine gland
(ii) Endocrine gland

28. Table 2 has three types of glands. Complete table by filling in the name and function of one hormone secreted by each gland.

Glands	Hormone	Function
Thyroid
Pancreas
Testes

c) Ways those hormonal responses differ from nervous responses

29. (a) (i) what is meiosis?
(iii) Give two parts in plants and two in animals where meiosis occur.
(b) What is the role of meiosis in living organisms?
(c) In a breeding experiment, yellow –flowered plants were crossed with blue-flowered plants of the same species and resultant offspring were all yellow-flowered. Without using symbols, explain the absence of blue flowed plants in F1 generation.

30. (a) What is meant by the carbon cycle?
(b) Describe how
(i) The level of carbon dioxide organisms during the carbon cycle.
(ii) Energy flows between organisms during the carbon cycle.
c) Explain why energy is continually lost along a food chain from a lower trophic level to a higher one.

31. (a) Giving two examples in each case, describe the different types of variation in living organisms.
(b) Explain how variation is important in natural selection

32. (a) What is meant by water pollution?
(b) Outline human’s activities which causes water pollution.
(c) How do water pollutants affect living organisms?

33. (a) Explains why bacteria are abundant in nature.
(b) Giving examples, explain the economic importance of bacteria.