Contains atoms (smallest unit of matter);

molecules (two or more atoms joined together)

Ex: DNA; Glucose

Basic structural and functional units of an organism that are composed of chemicals. 

Ex: Smooth, Muscle and Epithelial Cells

Groups of cells and materials surrounding them that work together to perform a specific function.

Ex: Epithelial Tissue (body surfaces); Connective tissues (blood vessels); Muscular (allows movement of body)

Different types of tissues are joined together having a specific function and usually have shapes

Ex: Stomach, skin, bones, heart, liver etc. 

Related organs with a common function

Ex: Digestive, Integumentary

Any living individual where all parts of the body function together

Ex: Human