Following are brief descriptions of five organ systems found in vertebrate animals.
Integumentary system: Skin, hair and nails; sweat and oil glands provide physical, chemical, and biological barriers that protect the body.
Immune system: Leukocytes (white blood cells), tonsils, adenoids, thymus, and spleen protect against disease by identifying and neutralizing pathogens (germs) and tumor cells.
Lymphatic system: Lymph nodes (found in many organs), lymph tissue transfers lymph (a liquid) for the removal of interstitial fluid from tissues, absorbs and transports fatty acids and fats to the circulatory system, and transports immune cells to and from the lymph nodes.
Endocrine system: Endocrine glands (hypothalamus, pituitary, thyroid, adrenal, and others) secrete hormones that stimulate reactions throughout the body to maintain glucose concentrations within normal ranges.
Renal system: Kidneys, ureters, bladder, and urethra maintain fluid and electrolyte balance and provide for excretion of urine.
Patient X suffers from a disorder in which the glucose in his blood is not being taken up by the muscles to be processed into useable energy, and so fat cells are being used for this purpose instead. A reliable indicator of this disorder is an excessive amount of sugar (glucose) in the urine.
Which of the five systems does this disorder involve?