i)

Light/lighted bulb/light ray(s)

ii)

No light would be seen/part of the cardboard B would be seen.

iii)

Light travels in a straight line and because cardboard B is shifted out of the straight line, the light is not seen again.

iv)

The lighted bulb/light/light rays(s).

v)

Linear/rectilinear propagation of light/light travels in a straight line.

vi)

i)

A → Highly inflamable/flammable/catches fire easily
B → Harmful/irritant
C → toxic/poison/poisonous
D → Danger

ii)

Highly inflammable substances (A)

1. Petrol
2. Kerosene
3. Gas/Liquefied Petroleum Gas (LPG)
4. Sodium
5. Ethanol
6. Thinner
7. Turpentine
8. Carbon disulphide

Harmful/irritant substances (B)

1. Sodium hydroxide
2. Mineral acids/Phenol/H₂SO₄/HNO₃
3. Aluminum sulphate
4. Calcium Hydroxide

Toxic/poisonous substances (C)

1. Cyanide
2. DDT
3. Mercury
4. Lead compounds

iii)

Places where the symbols D(Danger) can be found

1. Highways/roads
2. High voltage equipment
3. Laboratories
4. Construction sites

iv)

Advantages of hazard symbols

1. They warn us of danager so that we do not harm ourselves
2. They prevent accidents or damage of properties

i)

A → Incisor B → Premolar/molar/cheek tooth C → Canine

ii)

Shape of A(Incisor)

Is chisel shaped

Shape of B(Premolar)

Has flat and broad surface with cusps/ridges/projections

Shape of C(Canine)

(Bluntly) pointed/conical

iii)

Function of A(Incisor)

For cuttin/biting

Function of B(Premolar)

For grinding/chewing/crushing

Function of C(Canine)

For tearing

iv)

I → Enamel/Crown
II → Root

i)

A → Garden fork/digging fork/foot fork
B → Spade
C → Hand trowel
D → Hand fork
E → Watering can

ii)

Uses of A(Garden fork)

1. Turning/loosening soil
2. Stirring soil

Uses of B(Spade)

1. Turning soil
2. Collection of soil
3. Levelling of soil surface
4. Mixing of animal feeds

Uses of C(Hand trowel)

1. Transplanting seedlings
2. Earthing up vegetable crops
3. Heaping soil around vegetable crops
4. Spreading manure

Uses of D(Hand fork)

Stirring/Loosening soil in nursery beds/vegetable beds

Uses of E(Watering can)

Watering

i)

Ruminants are animals/mammals with four chambered stomach

OR

Ruminants are cud chewing animals.

ii)

Examples of ruminants

1. Goat
2. Sheep
3. Cow/cattle
4. Camel
5. Antelope
6. Deer
7. Giraffe

Note: the following are not ruminants.

Non-ruminant animals are animals with a single-compartment stomach

Non-ruminants

1. Pigs
2. Hippopotamus
3. Rabbit
4. Poultry
5. Horses
6. Dogs
7. Cats
8. Humans

i)

A force is that which changes a body's state of rest or uniform motion in a straight line

OR

A force is a pull or a push on an object.

ii)

Effects of forces on the body

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

i)

Ways in which the carbon cycle can be maintained

1. Photosynthesis
2. Decay and decomposition
3. Respiration
4. Avoiding burning
5. Avoiding animals feeding on plants/deforestation
6. Afforestation/tree planting

ii)

Environmental effect when the carbon cycle is disrupted

1. Green house effect
2. Global warming/melting of ice bergs/polar ice/rise in sea level

i)

The three sub-atomic particles

1. Protons
2. Neutrons
3. Electrons

ii)

Relative charge on each of the three sub-atomic particles

1. Protons → positive (+1)
2. Neutrons → no charge (0)
3. Electrons → negative (-1)

iii)

The particle formed when an atom loses an electron is cation/positively charged ion.

i)

Mixture is what is formed when two or more substances are put together/combine physically.

ii)

Why some mixtures are thoroughly stirred before they are used

Mixtures are thoroughly stirred to make a homegenous/uniform mixture

OR

Mixtures are thoroughly stirred to make even/uniform concentration

i)

Reflection of light is the bouncing of light from a surface.

ii)

Characteristics of the images formed by plane mirrors

1. It is erect (upright)
2. It is virtual
3. It is laterally inverted
4. Same distance behind mirror as object is in front of mirror
5. Same size and shape as the object

i)

Fertilizer is any substance which is applied to the soil or plant to supply nutrients for plant growth.

ii)

Examples of an inorganic fertilizer

1. Urea
2. Muriate of potash
3. Single super phosphate (SSP)/sulphate of ammonia
4. NPK

i)

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

ii)

Dangers of indiscriminate sex on humans

1. Acquiring sexually transmitted diseases
2. Unwanted pregnancy/becoming pregnant
3. Causing abortion

i)

Simple machine is a device that makes work easier/faster.

OR

Simple machine a device which enables a small force (effort) to overcome a large force (load).

ii)

Examples of a simple machine

1. Lever (Examples are a crowbar, claw hammer, a pair of pliers)
2. Wheel and axle (Examples are the steering wheel of a car, bicycle pedal)
3. Pulley (Examples are a pulley used in raising a load)
4. The inclined plane (Examples are ramps, staircases, hilly roads)
5. The wedge (Examples are knife, axe, plough)
6. Screw (Examples are A screw bolt)

i)

Rusting is the reaction of iron or iron containing substances with water/moisture and air/oxygen to form an oxide of iron.

ii)

Effects of rusting

1. It causes iron to lose its strength/structure resulting in accident
2. It can cause collapse of building and bridges resulting in maintenance cost
3. It causes iron to lose its lustre

i)

Food nutrients are substances which when taken in by living things help in performing of life activities

OR

Food nutrients are essential materials/substances present in food which when taken in by living things help in performing of life activities

ii)

Carbohydrate → Bread, maize
Fats and oil → Palm fruits, margarine
Protein → Beans, meat

i)

Effects of malnutrition in farm animals

1. Loss of weight/stunted growth
2. General body weakness
3. Reduced activity
4. Dullness
5. Less resistant to diseases
6. Reduced reproduction
7. Poor formation of bones

ii)

Viral diseases of farm animals

1. Rinder-pest
2. Newcastle
3. Gumboro
4. Fowl pox
5. Cow pox
6. Marek's disease
7. Swine fever
8. Bird flu
9. Foot and mouth disease

i)

Soil erosion is the washing away/removal of the top soil by water or wind

ii)

Methods of controlling soil erosion

1. Terracing
2. Strip cropping
3. Contour ploughing
4. Wind breaks/afforestation/tree planting
5. Mulching
6. Cover cropping
7. Practising crop rotation
8. Bush fallowing/land rotation

α)

Adaptation is the ability of an organism to survive in a given environment using special features

β)

Endangered species are plants and animals facing extinction/numbers are decreasing.

i)

Examples of hard water

1. Well water
2. Sea water/lagoon water
3. Borehole

ii)

Why it is advisable to drink hard water

1. It contains ions of calcium which are good for strong bones and teeth
2. It helps to reduce heart ailments

i)

Magnetic field is the area around a magnet where the effect of the force of a magnet can be felt/experienced.

ii)

Methods of making magnets

1. Hammering/strong heating in the earth's magnetic field
2. Stroking
3. Electrical
4. Induction

i)

ii)

Common solvent used in the home

1. Water
2. Alcohol
3. Turpentine
4. Kerosene
5. Petrol

i)

Ration is the amount/quantity of food allowed an animal for a day/specific period of time.

ii)

Dehorning is the removal of the horns of animals to reduce fighting among them.

i)

An element is a substance that is made up of atoms of the same kind.

OR

An element is a substance that cannot be broken down into any simplier form (by any known chemical means).

ii)

i)

Mixed farming is a type of farming in which animals and plants are produced on the same piece of land at the same time.

ii)

Mixed cropping is the cultivation of more than one type of crop on the same piece of land at the same time.