what are the major organs that make up each body system?
['Circulatory system: heart, blood, blood vessels, and lymphatics.', 'Digestive system: esophagus, stomach, small intestine, and colon.', 'Endocrine system: pituitary, thyroid, ovaries, and testes.', 'Immune system: organs (including lymphatics and spleen), special. ... ', 'Integumentary system: skin, hair, nails, and sweat glands.']