The document discusses several major organs in the human body, including the brain, lungs, stomach, liver, bladder, heart, and kidneys. The brain controls the body's functions. The lungs breathe in oxygen and breathe out carbon dioxide. The stomach digests food while the liver filters toxins from the blood. The bladder stores urine and the heart pumps blood throughout the body. The kidneys filter waste from the blood to be excreted as urine.