Chapter 24
Urinary System
By Boundless
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The kidneys are located at the rear wall of the abdominal cavity and they are protected by the ribcage.
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The cortex and medulla make up two of the internal layers of a kidney and are composed of individual filtering units known as nephrons.
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The renal veins drain the kidney and the renal arteries supply blood to the kidney.
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The nephron of the kidney is involved in the regulation of water and soluble substances in blood.
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Urine is formed in three steps: filtration, reabsorption, and secretion.
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Glomerular filtration is the renal process whereby fluid in the blood is filtered across the capillaries of the glomerulus.
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Regulation of GFR requires both a mechanism of detecting an inappropriate GFR as well as an effector mechanism that corrects it.
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Tubular reabsorption is the process by which solutes and water are removed from the tubular fluid and transported into the blood.
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Hydrogen, creatinine, and drugs are removed from the blood and into the collecting duct through the peritubular capillary network.
Urine is a sterile waste product composed of water soluble nitrogen products.
Normal urine consists of water, urea, salts, and pigments.
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Antidiuretic hormone (ADH) is produced by the pituitary gland to control the amount of water that is reabsorbed through the collecting ducts.
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Urinalysis is the process of analyzing urine for target parameters of health and disease.
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Clearance is a measurement of the renal excretion ability.
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The urinary organs include the kidneys, ureters, bladder, and urethra.
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The ureters are two tubes that drain urine from each of the kidneys into the bladder.
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The urinary bladder is a hollow, muscular, and distendible or elastic organ that sits on the pelvic floor.
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The urethra is a muscular tube that connects the bladder with the outside of the body and removes urine from the body.
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Micturition is the ejection of urine from the urinary bladder through the urethra to the outside of the body.
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In addition to the kidneys, the liver, skin, and lungs also have important roles in the excretion of waste from the body.