1. The following are the organ systems and their constituting organs: (1) Integumentary System, which consists of the skin and the associated structures such as hair, fingernails, toenails, sweat glands, and oil glands; (2) Skeletal System, which composes of the bones and joints of the body and their corresponding cartilages; (3) Muscular System, which contains the skeletal muscle tissues; (4) Nervous System, which includes the brain, spinal cord, nerves, and special sense organs like eyes and ears; (5) Endocrine System, which consists of the hormone-producing cells and hormone-producing glands such as the pineal gland, hypothalamus, pituitary gland, thymus, thyroid gland, parathyroid glands, adrenal glands, pancreas, ovaries, and testes; (6)Cardiovascular System, which comprises the blood, heart, and blood vessels; (7) Lymphatic System, which includes the lymphatic fluid and vessels, spleen, thymus, lymph nodes, tonsils, and cells that carry out immune responses (e.g., B cells, T cells, etc.); (8) Respiratory System, which contains the lungs and air passageways namely, pharynx, larynx, trachea, and bronchial tubes; (9) Digestive System, which composes of the gastrointestinal tract organs (mouth, pharynx, esophagus, stomach, small intestines, large intestines, and anus), and accessory organs that assist in the digestive processes such as the salivary glands, liver, gallbladder, and pancreas; (10) Urinary System, which consists of the kidney, ureters, urinary bladder, and urethra and; (11) Reproductive System, which contains the gonads (testes and ovaries) and the associated organs (uterine tubes, uterus, vagina, and mammary glands for female and epididymides, ductus deferens, seminal vesicles, prostate, and penis for males).
2. The respiratory system and urinary system are the organ systems that help regulate the acid-base balance of body fluids.