(i)

Types of forces apart from friction

1. Gravitational force/Force of gravity
2. Magnetic force
3. Electrostatic force
4. Centripetal force
5. Centrifugal force
6. Tension
7. Thrust
8. Weight
9. Cohesive force
10. Adhesive force
11. Surface Tension

(ii)

Effects of a force

1. It changes direction of a moving body
2. It increases speed of a body/causes a body to accelerate
3. It decreases speed of a body/causes a body to decelerate
4. It causes a moving body to stop
5. It causes a stationary body to move
6. It causes deformation/changes the shape of a body

(i)

Myopia/shortsight

(ii)

Eyeball is too long/eye lens too short so rays from far objects meet infront of the retina and therefore clear image is not formed.

(iii)

The defect can be corrected using a spectacle with concave or biconcave or diverging lenses which will refract the light to focus on the retina.

i)

Hormones are chemical substances produced by special endocrine/ductless glands in the body to enable certain organs function properly.

ii)

i)

2NH₄Cl + Ca(OH)₂ → CaCl₂ + 2NH₃(g) + 2H₂O

ii)

How to test for ammonia gas

1. Ammonia turns moist red litmus paper blue
2. Ammonia produces white fumes when it reacts with concentrated hydrochloric acid (HCl)

iii)

Uses of ammonia

1. For preparation of ammonium nitrate/fertilizers
2. Used in the textile industry
3. Used as a laboratory reagent

i)

Types of forces

1. Force of gravity
2. Weight
3. Magnetic force
4. Electrostatic force
5. Frictional force
6. Centripetal force
7. Viscous force
8. Tensional/Elastic force
9. Adhesion
10. Cohesion
11. Centrifugal force

ii)

1. Tensional/Elastic force
2. Force of gravity
3. Frictional force

(i)

Indiscriminate sex is the act of having sexual intercourse with any person or having many/multiple/different sexual partners.

(ii)

Reasons why teenagers indulge in indiscriminate sex

1. Peer pressure
2. Lack of parental guidance
3. Poor financial status of parents/poor homes
4. Lack of sex education
5. Weak morals/exposure to pornographic material

(i)

Sources of natural light

1. Sun
2. Fireflies
3. Stars
4. Lightening
5. Glow worm
6. Volcano

Note: the moon is not a source of natural light

(ii)

Sources of artificial light

1. Heated filament/electric bulb
2. Firecrackers
3. Torchlight/flashlight
4. Buring charcoal
5. Lantern
6. Satellite
7. Wood fire
8. Lamp

(i)

FeS → Iron (II) sulphide

(ii)

CO → Carbon (II) oxide

(iii)

Cu₂O → Copper (I) oxide

(iv)

NaOH → Sodium hydroxide

(i)

Differences between electrical insulators and electrical conductors

(ii)

Effects of illegal electrical connections in the home

1. Overload of power supply
2. Drop in voltage of electricity
3. Leads to frequent power cuts
4. Leads to electrocution/electric shock
5. May cause fire outbreak
6. May damage electrical appliances
7. Leads to loss of revenue to government

(i)

Condensation is the change from the gas state to the liquid state.

(ii)

Freezing is the change from the liquid state to the solid state.

iv)

Reasons

1. Presence of large/ single vacuole (IX)
2. Presence of cell wall (V)
3. Rectangular shape
4. Nucleus pushed to the side/periphery
5. Cytoplasm pushed to the side

v)

Differences between parts labelled I (Cell Membrane) and V (Cell Wall)

i)

(α) mass of irregular object (M) in I = 40 g
(β) Volume of water (V₁) in II = 40 cm³
(γ) Volume of water (V₂) in III = 60 cm³

ii)

Volume of the irregular object = 60 cm³ - 40 cm³ = 20 cm³

iii)

Density = $\frac{\mathrm{40\; g}}{\mathrm{20 }{\mathrm{cm}}^3}$ = 2 g/cm³ or 2 gcm^-3

iv)

Instruments for measuring mass of an irregular object

1. Beam balance
2. Top pan balance
3. Electronic balance

iv)

Precautions to be taken in performing the experiment

1. The object should be lowered gently into the water in the cylinder
2. Volume of the liquid should be read from the base of the meniscus or at the eye level
3. The measuring cylinder should be placed on a flat surface

i)

(α) chemical processes

II and III

(β) physical processes

I and IV

ii)

(α) Why chemical processes

1. The initial/original substance cannot be gotten back easily/irreversible
2. New substance formed
3. Change in mass
4. Accompanied by appreciable heat change

(β) Why physical processes

1. The initial/original substance can be gotten back easily/reversible
2. No new substance formed
3. No change in mass
4. Not accompanied by appreciable heat change

iii)

Examples of physical change

1. Expansion of metal on heating
2. dissolving sugar or salt in Water
3. Boiling of water
4. Melting of ice
5. Breaking/crushing of any Object

i)

ii)

Principles to consider when planning for rotational programme

1. Deep rooted crops should be followed by shallow rooted crops
2. Crops of the same family/class should not follow each other
3. Crops that use the same soil nutrients should not follow each other
4. Leguminous crops should be included in the cycle
5. A fallow period may be included in the crop rotation programme
6. Crops which attract the same diseases and pests should not follow each other

iii)

Reasons for selecting the crop named V (Soyabean)

1. Soyabean is a legume and therefore builds up soil fertility
2. Yam is a deep rooted crop and should be followed by soyabean which is a shallow rooted crop
3. Yam is a heavy feeder and must have taken good part of the nutrients
4. Yam and soyabean belong different classes of crops and therefore not likely to attract the same pests and diseases
5. Improves soil structure

iv)

Advantages of crop rotation

1. Increases soil fertility
2. Enhances soil structure
3. Prevents soil erosion
4. Improves soil nutrients and nutrient uptake regulation
5. Controls the spread of pests and diseases
6. Controls weed easily
7. There is effective use of the land
8. Harvest of different types of crops on the same piece of land

i)

Identification of labelled parts

I → womb(wall)/uterus
II → fallopian tube/oviduct
V → ovary
VI → vas deferens/sperm duct
VII → penis
VIII → testis

ii)

Function of III(Cervix)

Contracts/relaxes during child birth/protects foetus

Function of IV(Vagina)

1. Receives the penis/semen/sperm during sexual intercourse/for sexual intercourse
2. Passage of foetus
3. Passage of menstrual fluid

Function of VII(Penis)

Passage of sperm/semen/for sexual intercourse

iii)

Name of part where

iv)

Common infectious diseases that affect both the male and female reproductive system

1. Syphilis
2. Herpes (simplex virus)
3. Chancroid
4. Chlamydia
5. Gonorrhea/gonorrhoea
6. Candidiasis/whites/thrush

i)

Common name of devices

Garden/farm tools/farm implements/farming tool

ii)

Name of labelled devices

A → Mattock
B → Peg
C → Hand fork

iii)

Uses of A (Mattock)

1. Removing of stump roots/for stumping
2. Cutting off exposed plant roots

Use of B (Peg)

For making spots on land (for correct spacing of plants)

Uses of C (Hand fork)

1. For removing weeds on garden beds
2. To loosen hard soil surface/for stirring
3. For mixing fertilizers around plants

iv)

Effects of the use of the device C (Hand fork) on the soil

1. Improves aeration
2. Improves water entry/circulation in soil
3. Improves structure of soil

v)

Ways of prolonging the usefulness of the device labelled A (Mattock)

1. Clean tool after use
2. Use it for the right work/purpose
3. Repair broken handle
4. Keep in a cool dry place
5. Oil metallic part before storage
6. Sharpen cutting edges
7. Ensure metallic blade is tightly fitted to wooden handle
8. Keeping tools in termite free area

i)

Symbols of electronic components

ii)

Circuit diagram showing forward biasing

iii)

Effects of resistor on diode and LED

Resistor limits current in the circuit and thereby protects diode and LED from burning off.

i)

Observations made in laboratory activities

ii)

Suggested aim for the experiment

1. To demonstrate the method of preparation of mixtures
2. To determine whether a homogeneous mixture/solution or heterogeneous mixture/solution would be formed
3. To prepare a mixture/solution
4. To determine if the solute will dissolve/mix with the solvent/water to form a solution/mixture

iii)

Differences between activity I and III

iv)

Method of separation for the activity carried out in II

Use of separating funnel