1
Q
Chemical level
A
Atoms, molecules, organelles
2
Q
Cellular level
A
Single cell
3
Q
Tissue level
A
Groups of similar cells
4
Q
Organ level
A
Contains two or more types of tissues
5
Q
Organ system level
A
Organs that work closely together
6
Q
Organismal level
A
All organ systems combined to make the whole organism
