Living Environment Translated Arabic 2014 | Page 28

All living organisms are made up of cells. g. Multicellular organisms have a specific system of organization: 1. Cell- the smallest unit of an organisms 2. Tissue- a group of cells that work together to perform a specific function 3. Organ- a group of tissues that work together to perform a specific function 4. Organ-System- ( System) – a group of organs that work together to perform a specific function 5. Organism- a complete living thing