2.1 – Describe the levels of organisation within organisms: organelles, cells, tissues,
organs and systems.
Level of Organisation Description
Organelles Specialised structures within any cell.
Cells The smallest structural and functional unit of an organism.
Tissues A group of specialised cells.
Organs A group of specialised tissues.
Usually self-contained and carries out a specific vital function.
Systems A group of organs in the body with a common structure or function.