Nucleus: Stores genetic material and controls cell activities. Mitochondria: Produce energy for the cell in the form of ATP. Ribosomes: Synthesize proteins. Endoplasmic Reticulum: Synthesizes lipids and proteins; rough ER has ribosomes, while smooth ER does not. Golgi Apparatus: Modifies and packages proteins for transport. Lysosomes: Break down waste materials and cellular debris.