1.Chemical level: the simplest level
- at this level atoms combine to form molecules such as proteins. Molecules associate with others to form organelles which are components of cells

2. Cellular level
- all cells have specific functions and vary in size and shape.

Name the different levels of structural organization that make up the human body, and explain their relationships pg 3

3. Tissue level
- tissues are formed of similar cells that have a common function. The four types of tissue are epithelium, muscle, connective, and nervous tissue.

4. Organ level
- an organ is made up of at least two tissue types that performs a specific body function.

5. Organ system
- organs that work together to accomplish a common purpose. For example the heart and blood vessels work together to ensure circulation.

6. Organismal level
- represents all previous levels working together to promote life.