This document discusses the levels of organization of living things from atoms to organisms. It begins by explaining that all matter is made of atoms which combine to form molecules and cells. Cells make up unicellular and multicellular organisms. Unicellular organisms consist of a single cell and can be prokaryotic or eukaryotic. Multicellular organisms are made of many eukaryotic cells that differentiate and organize into tissues and organs to carry out specific functions needed for organism survival.