Renal system (1)

Renal system (1)

List organs of urinary system & their functions
1. Kidneys
  1. Regultion of blood pressure & volume
2. Ureters
  1. Transport urine from kidneys to bladder
3. Bladder
  1. Storage of urine
4. Nephron
  1. Urine production
Describe gross anatomy of kidney
1. Calyces leading to a pelvis
2. Outer cortex
3. Medulla made up of pyramids
4. @Hilus- renal artery enters, & renal vein & ureter exit
Describe the nephron
1. Functional unit of kidney
  1. Each kidney has over 1 mil.
2. Produces urine by
  1. Filtration
  2. Secretion
  3. Reabsorption
3. Renal corpuscle
  1. Glomerulus
  2. Glomerular capsule
4. Tubule
  1. Proximal tubule
  2. Loop of Henle
  3. Distal tubule
5. Empty their products into collecting ducts
Describe the process of urine formation
1. Filtration
  1. Molecules small enough will be pushed through capillary wall in glomerular capsule - due to pressure change, afferent arteriole bigger than efferent ateriole
    1. Produces filtrate (120mls/min)
      1. Contains wastes + useful molecules small enough
  2. Blood hydrostatic pressure 55mmHg
    1. - capsular pressure 15mmHg
      1. - Blood colloid osmotic pressure 30mmHg
        = Net filtration pressure 10mmHg
2. Reabsorption
  1. Useful small molecules lost in corpuscle filtration can be reabsorbed through the walls of tubule to the cappillaries
    1. Approx. 119mls filtrate is reabsorbed
3. Secretion
  1. Unwanted molecules missed during filtration can be secreted into tubule from capillary

Resource summary

	Created by Antonia Smith over 8 years ago