There are several types of cell organelles, each with specific functions: Nucleus: Contains the cell's genetic material (DNA) and controls cell activities. Mitochondria: Generate most of the cell's supply of adenosine triphosphate (ATP), used as a source of chemical energy. Ribosomes: Synthesize proteins. Endoplasmic Reticulum (ER): Involved in protein and lipid synthesis. Golgi Apparatus: Modifies, sorts, and packages proteins and lipids. Lysosomes: Contain digestive enzymes to break down waste materials and cellular debris. Vacuoles: Storage sacs for water, nutrients, and waste products. Chloroplasts (in plant cells): Conduct photosynthesis. Cell Membrane: Regulates the passage of substances into and out of the cell. Cell Wall (in plant cells, fungi, bacteria): Provides structural support and protection.