Directions: Complete the sentences by filling in the blanks with the correct word/s from the word box below. Write your answers in your Science activity notebook. 2. N Cell 4. Community Highest 1. The biological levels of organization of living things arranged from Word Box Lowest Organism Organs the simplest to most complex are: similar functions. 1a tissue organ 1b organism → population 1c ecosystem → biosphere 38 5. The Organ System Population Tissue are group of tissues in a living organism that performs 3. When cells of the same kind are grouped together, they are called type and live in the same area. refers to a group of organisms belonging to the same level of biological organization is called Biosphere.