Hierarchy
Atom
Molecule
Organelle
Cell
Tissue
Organ
Organ System
Organism
Atom
smallest particle of matter
Molecule
made of two atoms or more
Organelle
Microscopic structures that carry out functions of a cell
Cell
smallest unit of life
Tissue
similar cells that have a specific function
Organ
two or more tissues that work together for a function
Organ system
group of organs that work together for a function
Organism
complete individual formed of all organ systems