This document provides information about cells, including how to use a microscope and the key structures of plant and animal cells. It explains that a microscope has different lenses and parts that allow the user to focus on and magnify cells. Diagrams of onion cells viewed under a microscope are included. The main structures of animal cells are the cytoplasm, cell membrane, and nucleus. Plant cells also contain chloroplasts, a cell wall, and a large central vacuole. The document compares and contrasts the structures found in plant versus animal cells.