i)

Tilapia/Bony fish

ii)

I → mouth
II → operculum/gill cover
IV → scales/scale
V → lateral line

iii)

Habitat of tilapia/bony fish

1. Fresh water/river
2. Pond/fish pond
3. Brackish water/lagoon
4. Lake

iv)

Adaptation of fish

III (Pectoral Fin) → used for movement/swimming or pitching

VI (Eye) → for (wide) vision/seeing

i)

Soil profile

ii)

I → Top soil/humus
II → Subsoil
III → Weathered material/rock
IV → parent/(unweathered) rock/rock layer/bedrock

iii)

iv)

Effects of heavy rainfall on I (Top Soil/Humus)

1. Erosion
2. Leaching

i)

I → Cell
II → Key/switch
IV → (Standard) Resistor
VI → variable resistor/rheostat/resistance box

ii)

Energy transformation in parts of a circuit

iii)

S.I Units of current and voltage

iv)

Function of VI (Variable resistor/rheostat/resistance box)

1. Used to control/regulate current
2. Used to vary current

i)

Identification of solutions

ii)

Neutralization reaction

iii)

Salt/Neutral/Sodium chloride (Solution)

iv)

Both red and blue litmus papers would not change colour/there is no colour change/no effect on both red and blue litmus papers

v)

How to obtain salt (sodium chloride) from salt solution

Pour the resulting solution into a suitable container and allow to dry/heat to dryness/evaporate

i)

An ion is an atom/group of bonded atoms that has lost or gained electron(s) or a charged atom/group of bonded atoms

ii)

Methods of softening hard water

1. Boiling
2. Destillation
3. Addition of washing soda/Na₂CO₃/Sodium carbonate
4. Use of ion exchange resin/deionization

i)

Difference between pests and parasites

Pest is any organism which causes damage to crops/animals (beneficial to man) while a parasite is a living organism which lives on the surface/inside the body of another organism/host and gets its food from it and in so doing causing harm to the host.

ii)

Examples of pests and parasites

i)

Work is said to be done when a force moves a body through a distance in the direction of the force or is the product of force and distance moved in the direction of the force.

ii)

Work = Force x Distance

Force = 10 N
Distance = 5.2 m

Work done = 10 N x 5.2 m = 52 Joules(J)

i)

Malnutrition is a condition that occurs when a person is not obtaining enough nutrients or is a condition that results from eating a diet in which nutrients are either not enough/are too much such that the diet causes health problems

ii)

Symptoms of deficiency diseases

i)

Potential energy is the energy possessed by a body by virtue of its position (relative to others)

ii)

Mass = 10 kg
velocity = 2 ms^-1

Kinetic Energy (K.E) = $\frac{1}{2}$ x 10 kg x 2 ms^-1 x 2 ms^-1

K.E = 10 x 2 Joules = 20 Joules (J)

i)

Macro nutrients

1. Nitrogen (N)
2. Phosphorus (P)
3. Potassium (K)
4. Calcium (Ca)
5. Magnesium (Mg)
6. Sulphur

ii)

Micro nutrients

1. Copper (Cu)
2. Zinc (Zn)
3. Molybdenum (Mo)
4. Iron (Fe)
5. Boron (B)
6. Cobalt (Co)
7. Chlorine (Cl)
8. Manganese (Mn)
9. Sodium (Na)

i)

Hazard is a danger/risk that could result in physical harm to people/damage to property or is any source of potential damage/harm/adverse health effect on something/someone.

ii)

Precautions against hazard

1. Wearing of protective clothing/boots/goggles
2. Routine maintenance of equipment
3. Closing all taps before leaving the laboratory
4. Switching off all electrical points
5. Mounting hazard signs of dos and don'ts in the laboratory/working area etc.
6. Avoid skin and eye contact with chemicals
7. Use equipment only for its designated purpose
8. All containers must have appropriate labels. Unlabeled chemicals should never be used
9. Do not taste or intentionally sniff chemicals
10. Never consume and/or store food or beverages or apply cosmetics in areas where hazardous chemicals are used or stored
11. Wash exposed areas of the skin prior to leaving the laboratory
12. Do not work alone in a laboratory if the procedures being conducted are hazardous

i)

Weather is atmospheric conditions at a place over a short duration of time or day to day conditions/changes of the atmosphere/environment

ii)

Differences between weather and season

i)

Fertilse soil is a soil that has an abundance of plant nutrients/minerals organic matter to support plant growth or it contains all the major nutrients for basic plant nutrition as well as other to support plant growth.

ii)

Causes of loss of soil fertility

1. Loss of top soil by erosion
2. Nutrient mining/depletion/removal of nutrients by crops
3. Sand winning/physical degradation of soil/poor soil structure/water logging/compaction
4. Decreased soil bioactivity
5. Soil acidification/salinization/alkalization
6. Leaching
7. Overgrazing
8. Overcropping
9. Soil erosion
10. Excessive burning/bush burning/wildfires
11. Soil pollution/indiscriminate use of agrochemicals
12. Inefficient soil management practices

i)

Magnetic field is a region/area around a magnet/moving electric charge within which the force of magnetism acts/can be felt/experienced

ii)

Methods of making magnets

1. By induction
2. By stroking
3. By the use of electricity
4. By hammering/hitting

i)

calcium chloride → CaCl₂

ii)

copper (I) oxide → Cu₂O

iii)

nitrogen (IV) oxide → NO₂

iv)

ammonia → NH₃

i)

Physical properties of soil

1. Texture
2. Structure
3. Temperature
4. Colour
5. Permeability
6. Water
7. Capillarity
8. Organism
9. Drainage
10. Air
11. Strength/consistence
12. Porosity

ii)

Texture of clayey soil

It is smooth/slippery/sticky when wet

i)

Derrived quantities are quantities which are combination/multiples/ratios of base/fundamental quantities

ii)

S.I. units of area and volume

i)

Factors necessary for photosynthesis

1. Sunlight
2. Chlorophyll
3. Carbon dioxide
4. Water

ii)

Function of sunlight

Is to separate the hydrogen and oxygen atoms of water/provides energy

Functions of chlorophyll

Absorbs/traps light

Function of water

Splits into oxygen, hydrogen ions and electrons to replace the lost electrons/raw material/combines with CO₂ to produce food

Function of carbon dioxide

It's a raw material/used in splitting water/is reduced to sugar

i)

Soft water is water that lathers easily/readilt with soap/water which does not contain/contains negligible Ca²⁺/Mg²⁺/Ca/Mg ions/salt

ii)

Hard water is water that does not lather easily/readily with soap/water which contains Ca²⁺/Mg²⁺/Ca/Mg ions/salt