Eukaryote literally means “true nut” or “true kernel” in Greek. It is a term used to refer to organisms with complex cells that contain membrane-bound organelles and a membrane-bound nucleus. The nucleus of an eukaryotic cell is a membrane sac that houses the cell’s DNA. The DNA is bound up with histones to make chromosomes. A unique quality of eukaryotic cells is that they have a cytoskeleton. The cytoskeleton is a network of protein filaments that is anchored to the cell membrane. Therefore, it provides support, gives the cell its shape, and makes movement possible. Almost all eukaryotes contain complex organelles. For example, many are home to mitochondria. Mitochondria are organelles that function to perform aerobic respiration and to generate energy. Numerous eukaryotes also contain an endoplasmic reticulum (or ER). This organelle is a wide network of membranes that provides a transport system within the cell. Golgi bodies are other organelles present in some eukaryotic cells, particularly in secretory cells. They package cell products into vacuoles for transport to outside of the cell.