(a) Characteristics of living organisms
- Syllabus
- 2024
- Topic
- —
- Level
- —
Learning objectives
Recognise the shared characteristics of living organisms
Living organisms carry out a shared set of life processes. No single process is enough on its own; the complete pattern distinguishes living activity.
| Characteristic | What it means | Observable example |
|---|---|---|
| nutrition | obtaining materials needed for energy, growth and repair | a plant makes sugars; an animal feeds |
| respiration | releasing usable energy from nutrients in cells | energy supports muscle contraction or active transport |
| excretion | removing waste products made by metabolism | carbon dioxide is removed from an animal |
| response | detecting and reacting to a change in the surroundings | a shoot grows towards light |
| movement | changing position of the whole organism or part of it | an animal walks; a plant shoot bends |
| control of internal conditions | keeping the internal environment within workable limits | body temperature is regulated |
| reproduction | producing new organisms | cells or organisms form offspring |
| growth and development | permanent increase in size plus changes towards a mature form | a seedling increases in mass and forms new tissues |
The processes support one another: nutrition supplies raw materials, respiration releases energy, growth builds new material, and internal control keeps cellular conditions suitable for these reactions.
Respiration is a chemical process in cells, not simply breathing. Excretion removes metabolic waste; removal of undigested food is egestion. Movement does not require an organism to travel from place to place, because part of an organism can move or grow in a new direction.