General Science and Environmental Awareness
General Science and Environmental Awareness covers basic physics, chemistry, biology, health and ecology. The exam favours direct definitions, units, laws and environmental cause-effect relationships.
Core rules and concepts
- Physics: SI units; Newton's three laws; work = force x displacement; power = work/time; Ohm's law V = IR; sound needs a medium; light reflection/refraction.
- Chemistry: acids pH < 7, bases > 7, neutral = 7; periodic table groups; common salts; combustion needs oxygen.
- Biology: cell as unit; human systems; vitamins and deficiency diseases; communicable vs non-communicable diseases.
- Environment: food chains, 10% energy law, biodiversity, greenhouse gases (CO2, CH4, N2O), ozone depletion by CFCs, pollution types, renewable energy.
Worked example
A grassland food chain has 10,000 J at the producer level. Using the ten-percent law, energy available to the tertiary consumer is: Producer 10,000 J -> primary consumer 1,000 J -> secondary 100 J -> tertiary 10 J. Answer: 10 J. The rule applies to energy flow, not total biomass.
Traps that cost marks
Ozone depletion (CFCs) is not the same as global warming (greenhouse gases). pH 7 is neutral, not 'acidic'. Do not confuse biodegradable with non-biodegradable waste. In physics, convert cm to m and minutes to seconds before calculating. Deficiency diseases: night blindness from vitamin A, scurvy from vitamin C, rickets from vitamin D.