Renal System

There are two ureters (from kidney to bladder) and one urethra (from bladder to outside).

Uraemia. The other terms describe the volume of urine produced. Anuria = no urine; polyuria = far more than normal; oliguria, less than normal.

Arterioles have smooth muscle in their wall which allows them to constrict and dilate, hence adjusting the flow through them and consequently the blood pressure within them.

Sodium and chloride leave from the ascending limb not the descending limb.

Antidiuretic hormone prevents diuresis (decreases urine formation) by causing more water to be reabsorbed from the filtrate as it passes through the collecting duct.

Cortical nephrons are situated almost entirely within the cortex, while the far less numerous juxtamedullary nephrons have their glomeruli adjacent to the medulla and extend their loop of Henle into the medulla.

Blood concentration rises as water is lost from the body by evaporation, and urine is formed. ADH causes water to be reabsorbed from the kidney filtrate, so the rise in blood concentration would slow as more water is returned to the blood rather than being filtered out into urine. Blood concentration would not fall until some water has been drunk.

Hilum is the name of the point of attachment between an organ and its supply services.

Solutes are filtered out of the blood in the glomerular capillaries into the Bowman’s capsule. Together the two structures form the renal corpuscle.

ADH increases the permeability of the collecting duct to water. Angiotensin II stimulates the adrenal glands to release aldosterone and promotes peripheral vasoconstriction.