OC4 - renal system Flashcards
what are the components of the kidney?
medulla
cortex
faccia
adipose tissue
ureter
renal pelvis
renal hilum - renal vein, renal artery, renal nerve
where are nephrons located?
in the medulla and the cortex
what is the function of the nephron?
the main filtration unit
what are the components of a nephron?
afferent arteriole
efferent arteriole
renal corpuscle - glomerulus and bowmans capsule. contains juxtaglomerular cells involved in BP regulation
proximal convulated tubule - reabsorption
loop of henle - countercurrent mechanism
distal convulated tubule - secretion
what is the countercurrent mechanism?
takes place in the loop of henle
ascending limb - permeable to ions
descending limb - permeable to water
what are the functions of the renal system?
endocrine metabolic
endocrine secretory
excretory
homeostatic
what is the endocrine metabolic function of the renal system?
converts calcidiol to calcitriol
what is the endocrine secretory function of the renal system?
juxtaglomerular cells produce renin which is involved in the regulation of blood pressure
endothelial cells of peritubular capillaries in the renal cortex produces erythropoiten which is involved in the formation of red blood cells.
what is the excretory function of the renal system?
excretion of waste
what is the homeostatic function of the renal system?
osmoregulation - water balance and electrolyte balance
acid-base balance
blood pressure regulation
what is filtration within the renal system?
occurs in the renal corpuscle of nephrons
endothelial cells, basement membranes, podocytes, filtrate.
what is the function of endothelial cells in filtration in the renal system?
restricts blood cells
what is the function of basement membranes in filtration in the renal system?
restricts large proteins
what is the function of podocytes (walls) in filtration in the renal system?
restricts intermediate proteins
what is the filtrate in the renal system?
water and small solutes such as glucose, amino acids and ions
what is absorption in the renal system?
occurs in the proximal convulated tubule glucose and proteins are all reabsorbed
what is secretion in the renal system?
occurs in the distal convulated tubule
main waste product is urea
all creatine is excreted
what is the process of blood pressure regulation?
renin is produced by juxtaglomerular cells in the kidney and travels to the liver where it activates angiotensinogen to produce angiotensin 1
angiotensin 1 travels to the lungs where ACE (angiotensin converting enzymes) convert it to angiotensin 2 - a general vasoconstrictor which increases blood pressure.
angiotensin 2 travels to the adrenal gland where it stimulates aldosterone
aldosterone retains sodium which increases Na+ causing an increas in H2O so an increase in blood volume and therefore an increase in blood pressure
what is acidosis?
pH below 7.35
increased CO2 and H+
decrease in pH
chemoreceptors detect change
increase in breathing rate and kidneys secrete H+
decrease in CO2
increase in pH
what is alkalosis?
pH above 7.45
decreased CO2 and H+
increase in pH
chemoreceptors detect change
decrease in breathing rate and kidneys secrete HCO3-
increase in CO2
decrease in pH
what is respiratory acidosis/alkalosis?
failure of the respiratory system
kidneys fix
what is metabolic acidosis/alkalosis?
failure of the kidneys
respiratory system fixes.
