This is a High School Biology Lesson on Cells. The Cell is defined, as well as the Cell Theory. Differences in Prokaryotic and Eukaryotic cells are discussed. Basic cell structure is described including these organelles: cell membrane, nucleus, nucleolus, nuclear membrane, ribosomes, endoplasmic reticulum, golgi, mitochondria, lysosomes, cytoskeleton, cilia, flagella, cell wall, vacuoles and chloroplasts.