Module 6 Flashcards
what does the urinary system consist of
- kidneys
- ureters
- urinary bladder
- urethra
function of the kidneys
- maintain the volume and composition of the body’s extracellular fluids
- process blood, retain useful substances whilst forming urine as a waste product
list the functions of the urinary system
- regulates
- excretes waste
- endocrine
- produces
Functions of the urinary system - regulates
- regulates fluid volume to control blood water content and thus blood volume
- regulates solutes and electrolytes
- regulates acid base balance to control blood pH
Functions of the urinary system - excretes waste
- excretes metabolic waste e.g. urea
- excretes foreign waste e.g. drugs
Functions of the urinary system - endocrine
- erythropoietin (hormone that stimulates RBC)
- renin (maintenance of blood pressure)
Functions of the urinary system - produces
- produces active vitamin D
- produces glucose to maintain levels when fasting
how are the kidneys supplied with blood
by the renal arteries; derived from branches of the ABDOINAL AORTA
(drains through renal veins into inferior vena cava)
what are the 3 regions of the kidney structure
- cortex
- medulla
- pelvis
Kidney - Cortex
outer region containing cortical nephrons
Kidney - Medulla
cone shaped tissue called renal pyramids
Kidney - Pelvis
- funnel shape continuous with ureter
- drains papillae through minor calcyces then to major calyces
The Nephron - Renal Corpuscle
capillaries and glomerular capsule are specialised for filtration
The Nephron - Renal tubule
- Proximal convoluted tubule (PCT)
- Distal convoluted tubule (DCT)
nephron
urine forming units of the kidney
what are the 2 major groups of nephrons
- cortical nephrons (85%)
= juxtamedullary nephrones (renal medulla, concentrates urine)
what does blood pass through to enter and exit the gomerulus
in through afferent arteriole and out by efferent arteriole
what are the 3 major processes of urine production
- Glomerular filtration
- Tubular reabsorption
- Tubular secretion
describe pertibular capillaries
close to renal tubes
low pressure, prous capillaries
readily absorb solutes and water
describe vasa recta
long straight vessels serving juxtamedullary nephrons to form concentrated urine
what does blood pressure drive
filtration
what does the filtration membrane of the glomerulus consist of
- perforated endothelium of golmerular capillaries
- epitheelial cells or podocytes of the inner layer of capsule
- collagenous basement membrane
define glomerular filtration
a non selective process in which hydrostatic (blood) pressure forces fluid through the glomerular membrane
what does the filter allow to pass
free passage of water and most solutes, including ions, glucose,