The seven characteristics of life
The seven characteristics of life
- Every living thing carries out seven life processes.
- Remember them with MRS GREN.
- Examiners want the exact definitions, so learn them.
Practice
The seven characteristics of living organisms can be remembered as:
MRS GREN = Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, Nutrition.
MRS GREN
- Movement — changing position or place.
- Respiration — chemical reactions in cells that release energy from nutrients.
- Sensitivity — detecting and responding to changes.
- Growth — a permanent increase in size and dry mass.
- Reproduction — making more of the same kind of organism.
- Excretion — removing the waste products of metabolism (and excess substances).
- Nutrition — taking in materials for energy, growth and development.
Practice
Respiration is:
Respiration is the cellular energy-releasing reactions — not the same as breathing.
Practice
Excretion is:
Excretion removes metabolic waste; removing undigested food (egestion) is different.
Common traps
- Digestion is not one of the seven — it is part of nutrition.
- Breathing is not the same as respiration (respiration is the chemical reactions in cells).
Practice
Which is NOT one of the seven characteristics?
Digestion is part of nutrition, not a separate characteristic; breathing is not on the list either.
You've got it
Key idea
- the seven characteristics: MRS GREN (Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, Nutrition)
- respiration = energy-releasing reactions in cells (not breathing); excretion = removing metabolic waste
- digestion and breathing are not on the list