Final answer:
Isotopes are used in medicine for diagnostic imaging and treatment. They emit ionizing radiation that helps locate damaged tissues and visualize specific organs. Examples include technetium-99 for damaged heart, liver and lung tissues, and iodine-131 for the thyroid gland.
Step-by-step explanation:
Isotopes play a significant role in medicine, particularly in the field of nuclear medicine. Radioactive isotopes, such as technetium-99, thallium-201, iodine-131, and sodium-24, are used for diagnostic imaging and treatment. These isotopes emit ionizing radiation, which can be detected to locate damaged tissues or to visualize specific organs. For example, technetium-99 is preferentially absorbed by damaged heart, liver, and lung tissues, while iodine-131 concentrates in the thyroid gland. These isotopic applications have greatly improved medical diagnosis and treatment.