Learn: Compare plant, animal and specialised cells; use microscopes.

Key principle: Cells form tissues, organs and systems.

Example: A root-hair cell has a long extension for absorption.

Avoid: Do not confuse cell wall with cell membrane.

Learn: Study nutrients, balanced diet, enzymes and the alimentary canal.

Key principle: Enzymes work best at an optimum temperature and pH.

Example: Amylase breaks starch into simpler sugars.

Avoid: Digestion is breakdown; absorption moves nutrients into blood.

Learn: Understand blood, heart, vessels, plant xylem and phloem.

Key principle: Arteries carry blood away from the heart.

Example: Xylem transports water and mineral ions upward.

Avoid: Veins are not always deoxygenated; pulmonary vein is an exception.

Learn: Distinguish aerobic and anaerobic respiration.

Key principle: Aerobic respiration releases energy from glucose using oxygen.

Example: Glucose plus oxygen produces carbon dioxide and water.

Avoid: Respiration occurs in cells; breathing moves air.

Learn: Study reproductive systems, fertilisation, pregnancy and plant pollination.

Key principle: Fertilisation is fusion of male and female nuclei.

Example: Pollen transfers from anther to stigma during pollination.

Avoid: Pollination is not the same as fertilisation.

Learn: Study germination, growth measurement, hormones and life cycles.

Key principle: Germination needs water, oxygen and suitable temperature.

Example: A seed uses stored food before leaves photosynthesise.

Avoid: Light is not required for every seed to germinate.

Learn: Use food chains, cycles, populations and conservation ideas.

Key principle: Energy decreases along a food chain.

Example: Grass to grasshopper to frog shows producer then consumers.

Avoid: Arrows show energy transfer, not who chases whom.

Learn: Compare communicable and non-communicable disease and prevention.

Key principle: Pathogens include bacteria, viruses, fungi and protoctists.

Example: Vaccination prepares immune memory.

Avoid: Antibiotics do not kill viruses.

Learn: Explain states, diffusion and changes using particles.

Key principle: Heating increases particle kinetic energy.

Example: Diffusion is faster in gases than liquids.

Avoid: Particles themselves do not expand.

Learn: Classify substances and choose separation methods.

Key principle: Compounds contain elements chemically combined in fixed ratios.

Example: Filtration separates insoluble solid from liquid.

Avoid: Melting cannot separate a dissolved solid.

Learn: Use protons, neutrons, electrons and ionic or covalent bonding.

Key principle: Atomic number equals proton number.

Example: Sodium forms Na+ by losing one electron.

Avoid: Ions form by electron transfer, not proton movement.

Learn: Use indicators, pH, neutralisation and salt preparation.

Key principle: Acid plus base produces salt and water.

Example: Hydrochloric acid plus sodium hydroxide makes sodium chloride and water.

Avoid: Strong and concentrated do not mean the same thing.

Learn: Balance equations; study rates, catalysts and energy.

Key principle: A catalyst speeds reaction without being used up.

Example: Powder reacts faster because of greater surface area.

Avoid: A catalyst does not increase the final amount of product.

Learn: Use reactivity, extraction, corrosion and alloy ideas.

Key principle: A more reactive metal displaces a less reactive metal.

Example: Zinc displaces copper from copper sulfate.

Avoid: Rusting needs both oxygen and water.

Learn: Use SI units, instruments, graphs and experimental accuracy.

Key principle: Repeat readings and calculate a mean to reduce random error.

Example: Speed may be measured in metres per second.

Avoid: Precision does not guarantee accuracy.

Learn: Calculate speed, acceleration and interpret motion graphs.

Key principle: Speed equals distance divided by time.

Example: 150 m in 30 s gives 5 m/s.

Avoid: A flat distance-time graph means stationary.

Learn: Calculate work, power and energy transfers.

Key principle: Work equals force times distance in force direction.

Example: 50 N moving 3 m does 150 J of work.

Avoid: Power is rate of energy transfer, not total energy.

Learn: Study conduction, convection, radiation and expansion.

Key principle: Heat flows from hotter to cooler regions.

Example: Dark dull surfaces are good absorbers and emitters.

Avoid: Temperature and heat are different quantities.

Learn: Use circuits, current, voltage, resistance and electromagnets.

Key principle: Voltage equals current times resistance.

Example: At 2 A through 6 ohms, voltage is 12 V.

Avoid: Current is not used up in a series circuit.

Learn: Describe wave properties, reflection, refraction and sound.

Key principle: Wave speed equals frequency times wavelength.

Example: A 5 Hz wave of wavelength 2 m travels at 10 m/s.

Avoid: Sound cannot travel through a vacuum.