Characteristics and classification — Cambridge IGCSE Combined Science
The seven characteristics of living organisms (MRS GREN) and the definition of each one.
Revision notes
1 short note, in the order of the specification. Each one in short:
The seven characteristics of living organisms are movement, respiration, sensitivity, growth, reproduction, excretion and nutrition, remembered as MRS GREN. Every living organism shows all seven, while a non-living thing may show some but never all. Growth is a permanent increase in size and dry mass, and excretion is the removal of metabolic waste, not the egestion of faeces.
Exam questions
2 exam-style questions (5 marks), each with its mark scheme.
Answer the questionsFlashcards
4 cards: flip them, mark what you knew, and practise the rest.
Practise the cardsMind map
The whole of characteristics and classification of living organisms on one page, so you can see where this subtopic fits.
Open the mind mapPrint it
Free PDFs to print or save.
Quick check questions
What is excretion?
Show answer
The removal of the waste products of metabolism and substances in excess of requirements.
Written and checked against the Cambridge IGCSE Combined Science (0653) specification · Updated October 2026