Characteristics of Living Organisms | Biology for GCSE/IGCSE - Year 11 PDF Download

Characteristics of Living Organisms

• Movement: Movement is an action by an organism or part of an organism causing a change of position or place.
• Respiration: Respiration involves the chemical reactions that break down nutrient molecules in living cells to release energy for metabolism.
• Sensitivity: Sensitivity refers to the ability to detect or sense stimuli in the internal or external environment and to make appropriate responses.
• Growth: Growth is a permanent increase in size and dry mass by an increase in cell number or cell size or both.
• Reproduction: Reproduction encompasses the processes that create more of the same kind of organism.
• Excretion: Excretion involves the removal from organisms of toxic materials, waste products of metabolism, and substances in excess of requirements.
• Nutrition: Nutrition involves the intake of materials for energy, growth, and development. Plants require light, carbon dioxide, water, and ions; animals need organic compounds, ions, and usually water.

Use this mnemonic to help you remember these processes:

MRS. H. GREN stands for the essential characteristics of living organisms:

• Movement (M)
• Respiration (R)
• Sensitivity (S)
• Homeostasis (H)
• Growth and Development (G)
• Reproduction (R)
• Excretion (E)
• Nutrition (N)