This document discusses the structures and functions of prokaryotic and eukaryotic cells. It describes the key differences between prokaryotic and eukaryotic cells, including that prokaryotes lack internal compartments while eukaryotes have a nucleus and organelles. It also summarizes the roles of important eukaryotic cell structures like the cytoskeleton, cell membrane, nucleus, ribosomes, endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria, and characteristics of plant cells such as the cell wall, chloroplasts, and central vacuole.