Levels of Organization

Cell

• The basic, & smallest unit of all forms of life.

Cell

• The basic, & smallest unit of all forms of life.

​– Ex. A neuron – the cells your nerves are made of.

Tissue

• A group of similar cells that perform a particular function.

Tissue

• A group of similar cells that perform a particular function.

• ​Ex. The nervous tissues & connective tissues in muscles.

Organ

• A group of tissues grouped together to perform a function.

Organ

• A group of tissues grouped together to perform a function.

• ​Ex. Your heart!

Organ System

• A group of organs that work together to perform closely related functions.

Organ System

• A group of organs that work together to perform closely related functions.

• ​Ex. The stomach, small intestines, & large intestines work together as the digestive system to break down food & take in nutrients.

Organism

• Living Thing

• ​Ex. YOU! (Humans)