- maintaining blood pressure
- blood filtration
- hormone secretion
- waste excretion
- pH maintenance
Structure Overview
- Two kidneys in humans
- bean-shaped
- 10-cm long
- made of tubules and ducts that carry urine
- contain a dense network of capillaries
- cortex, medulla, pelvis:
Urine:
- solution of metabolic waste
- contains water, salt, sugars, urine/urea, and other toxins
Nephron
- Basic unit of the kidney
- about a million of nephrons make up one kidney
- consists of tubules and ducts surrounded by blood vessels:
- afferent arteriole: carries blood to glomerulus
- capillaries: surround glomerulus
- efferent arteriole: capillaries converge and exit the the glomerulus
- peritubular capillaries: surrounds proximal and distal tubes
- vasa recta: surrounds loop of henle; countercurrent
