Pills and stethoscope. The pills (lower centre) are gelatin capsules containing medical drugs to treat illnesses. The capsules dissolve in the stomach to release their contents. The shape of the capsules makes it easier to swallow them. The stethoscope (upper centre) is used to listen to sounds within the body. The round component seen here contains a diaphragm that transmits the sound to earpieces (not seen). A stethoscope is usually used to diagnose disorders of the heart and lungs.