The seven characteristics of living organisms

The seven characteristics of living organismsSpec 1.1.1

Every living organism, from a bacterium to a blue whale, shows seven characteristics. A non-living thing, such as a car or a flame, may appear to show some of them, but never all seven.

Movement

an action by an organism or part of an organism causing a change of position or place

Respiration

the chemical reactions in cells that break down nutrient molecules and release energy for metabolism

Sensitivity

the ability to detect and respond to changes in the internal or external environment

Growth

a permanent increase in size and dry mass

Reproduction

the processes that make more of the same kind of organism

Excretion

the removal of the waste products of metabolism and substances in excess of requirements

Nutrition

the taking in of materials for energy, growth and development

The first letters spell MRS GREN: Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, Nutrition. Learn each definition word for word, because Cambridge mark schemes follow the syllabus wording.

Points that are often marked

• Plants move too. A plant moves when its leaves or flowers change position, even though the whole plant stays in one place.
• Growth means a permanent increase in size and dry mass. A balloon gets bigger when inflated but does not grow.
• Excretion is not the same as egestion. Faeces are undigested food that never entered the body's cells, so they are not metabolic waste.
• Examples of excretion: carbon dioxide from respiration, urea from the breakdown of excess amino acids, and oxygen from photosynthesis in plants.