In respones to changes e.g. the presence of a predator, to find food or mate. Parts of plants move very slowly e.g. to obtain more light for photosynthesis (achieved by growth)
Producing offspring. This prevents extinction of the species
The ability to sense and respond to changes in the surroundings. The term 'irritability' is sometimes used instead.
An increase in size, mass and complexity of an organism.
The breakdown of food in cells to release energy.
Getting rid of waste products made by chemical reactions in cells.
This involved feeding by obtaining nutrients for growth, energy and maintaining health. Plants make thier own food using photosynthesis, by obtaining simple nutrients (water and carbon dioxide) and light energy.
Things to remember
1. Do not confuse respiration with breathing.
2. Do not use faeces or defecation as an example of excretion (faeces is undigested food and it has not been formed through the metabolic processes).