Review and Reinforce Body Organization
Understanding Main Ideas
The illustration below shows the levels of organization in a reptile. The levels are
numbered 1-4, with 4 being the highest level and 1 being the lowest level. Match the
items below the illustration with the number that represents the lowest appropriate
level of organization in the illustration.
1. tissue
3 _
2. an object consisting of several different tissues L
3. the smallest unit of the body
4. group of organs that operate as a system