21: The Urinary System
Gross Anatomy of Urine Transport
- Identify the ureters, urinary bladder, and urethra, as well as their location, structure, and histology
- Compare and contrast male and female urethras
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- 21.1: Urethra
- This page discusses the anatomy and function of the urethra, highlighting differences between males and females. It describes the urethra's role in urine transport from the bladder and its structure, including the types of epithelial tissue present. It notes that voiding involves both involuntary and voluntary sphincters.
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- 21.2: Bladder
- This page discusses the urinary bladder's role in urine collection, its anatomical differences between genders, and its compression during pregnancy. The bladder is a distensible organ made of detrusor muscle and transitional epithelium, capable of holding 500-600 mL. Aging may reduce bladder strength, but voluntary abdominal muscle contractions assist in emptying the bladder and are also beneficial during defecation and childbirth.
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- 21.3: Ureters
- This page explains the anatomy and function of the kidneys and ureters, located retroperitoneally, with the bladder dome covered by peritoneum. Urine is made in the kidneys, moves to the bladder through the ureters, utilizing peristalsis. The ureters, approximately 30 cm long and lined with transitional epithelium, prevent urine reflux thanks to their oblique bladder entry.
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- 21.4: Gross Anatomy of the Kidney
- This page provides detailed information about the kidneys, including their anatomical location, protection, weight, and size. It describes the internal structure, highlighting the renal cortex, medulla, renal columns, and lobes. Additionally, it explains the function of nephrons, which filter blood and manage essential substances through a unique portal system involving an arteriole between capillary networks.
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- 21.5: Microscopic Anatomy of the Kidney
- This page explains that nephrons are the kidneys' functional units, essential for filtering blood and urine production through filtration, reabsorption, and secretion. They help maintain homeostasis, regulate blood pressure, produce red blood cells, and absorb calcium. The renal corpuscle, comprising the glomerulus and Bowman’s capsule, is pivotal in filtration, using a filtration membrane with podocytes and capillaries to allow selective plasma movement into the nephron for urine formation.
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- 21.6: Exercises
- This page provides lab exercises on kidney and urinary system anatomy and histology, focusing on identification and labeling tasks for structures like kidneys, adrenal glands, and blood vessels. It emphasizes renal anatomy, including the cortex, medulla, and nephron parts, as well as histological features such as arterioles and capillaries, aiming to enhance understanding of the urinary system's functional anatomy.
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- 21.7: MODELS- Kidney, Nephron, Torso and Hemi-Pelvis
- This page provides an overview of the anatomy and blood supply of the kidneys and urinary system, discussing the renal artery, nephron structure, ureters, and urinary bladder. It highlights important kidney components like the renal capsule and pyramids, and includes histological details on the epithelium and muscle tissue found in the kidneys, bladder, and ureters.