cells to organ systems

• multicellular organism - made of more than one cell
• example of an organ system : stomach liver, small and large intestine work together to digest food
• cell -> tissue -> organ -> organ system -> organism
• tissue = group of cells working together to preform a specific function
• circulatory system hierarchy - cell = red blood cells , tissue = muscle tissue, organ = heart , organ system = circulatory system, organism = human