(a) Describe six protective adaptations used by animals against predation and give one example in each case.
(b)(i) What is pollution?
(ii) State six human activities which cause pollution.
(a) Six protective adaptations used by animals against predation, with one example each
- Camouflage (protective/cryptic colouration): body colour blends with the surroundings so the animal is not easily seen. Example: the green grasshopper on green grass.
- Warning (aposematic) colouration: bright colours warn predators that the animal is poisonous or distasteful. Example: the brightly coloured wasp.
- Mimicry: a harmless animal resembles a dangerous or distasteful one and so is avoided. Example: the hoverfly mimicking a bee.
- Possession of a protective covering/armour: a hard shell or scales shields the body. Example: the tortoise withdrawing into its shell.
- Chemical/offensive defence: release of poison, sting or foul-smelling substance. Example: the bee's sting (or the millipede's repellent fluid).
- Behavioural defences such as feigning death or autotomy: the animal pretends to be dead, or sheds a body part. Example: the lizard casting off its tail (autotomy) to escape.
Others: living in groups/herding, and burrowing/hiding.
(b)(i) What is pollution?
Pollution is the release into the environment (air, water or soil) of substances or forms of energy in quantities harmful to living organisms, thereby making the environment dirty, unhealthy or unsuitable for life.
(b)(ii) Six human activities which cause pollution
- Burning of fossil fuels by vehicles and factories, releasing smoke and gases into the air.
- Discharge of untreated sewage into water bodies.
- Dumping of industrial effluents and chemical wastes into rivers.
- Indiscriminate disposal of refuse and solid waste.
- Excessive use of fertilizers and pesticides on farms.
- Oil spillage from tankers and pipelines.
Also: mining activities and noise from machines.