module 12 renal anatomy Flashcards
Intake triggered by
thirst
inc. concentration of extracellular fluid (osmolality)
dec. circulating vlood volume
excretion happens through
urinary tract - largest vol. excreted bowels - normal bowel function - inc. with diarrhea lungs - exhalation skin - sweating insensible perspiration
function of kidney
filter blood
hilus
concave portion of kidney
renal pelvis
Leaves kidney through hilus
Collecting area for urine that drains from collecting ducts of nephrons
urinary system
kidneys
ureters
bladder
urethra
kidneys
located in retroperitoneal space in posterior abd.
ureters
urine drained here by gravity from kidney
- uses peristalsis to move urine to bladder
urinary bladder
urine storage
2 parts:
body
neck
urethra
drains bladder when internal and external sphincters are relaxed
body of bladder
stores urine
made up of smooth muscle (detrusor muscle_
- extends in all directions, contracts as one to empty bladder
renal medulla
contains 8-18 pyramids, bases adjacent to cortex, apices (papillae) open into minor calices
minor calices
collect urine that drains from papillae
pyramids consist of
collecting tubules
collecting ducts
long loops of henle
vasa recta
vasa recta
capillaries around loops of henle
cortex
outer rim of kidney
- contains all glomeruli and 85% of nephron tubules
- 15% of nephrons send loops of henle deep into medulla: juxtamedullary nephrons
Kindey SNS innervation
renal vasoconstriction
renin release
Renal blood flow arterial side
abdominal aorta ->
renal arteries ->
several interlobar arteries (renal columns adjacent to pyramids ->
arcuate arteries (along base of pyramid/ cortical medullary border) ->
small interlobular arteries (penetrate cortex) ->
afferent arterioles (branches in cortex) ->
glomerular capillaries ->
efferent arterioles ->
peritubular capillaries (wrap around convoluted tubules)
reneal blood flow venous side
peritubular capillaries -> interlobular venules -> interlobular vein -> renal vein -> vena cava
nephron
functional unit of kidney
- filtration of water-soluble substances form blood
- reabsorption of filtered nutrient, H20, and electrolytes
- secretion of wastes or excess substances
filtration
blood to glomerulus -> proximal convoluted tubule
- glomerulus negatively charged
- negative ions and proteins are not filtered through
reabsorption
fluids, electrolytes, and solutes reabsorbed from tubule to blood
secretion
from blood to tubules
excretion
filtrate from kidneys -> bladder to be excreted
functional segments of nephron
glomerulus proximal convoluted tubule descending loop of henle ascending loop of henle distal convoluted tubule collecting tubule
Glomerulus functions
filters fluid from blood into bowman’s Capsule
prevents passage of blood cells and proteins
blood -> nephron tubule
- formed by capillary tuft (lies between afferent and efferent arterioles) and bowman’s capsule
proximal convoluted tubule
Bowman’s capsule drains here
High ATP requirement for reabsorption
transport 2/3 of filtered H2O and electrolytes and all of the filtered bicarb, glucose, amino acids, and vitamins from filtrate to interstitium
descending loop of Henle
only permeable to water -> into interstitium
transports water; delivers a concentrated filtrate to ascending loop of Henle
ascending loop of Henle
nonpermeable to water
actively transports Na, K, Cl, into interstitium to produce a hypoosmotic filtrate and high interstitial osmolality
distal convoluted tubule
transports Na, Cl, water, and urea
responsive to aldosterone, angiotensin II, ANP
site of macula densa regulation of GFR
secretes H and K
collecting tubule transports/secretes
passively transports H2O under influence of ADH
secretes H and K
Bowmans capsule components
parietal layer
inner layer (viseral)
basement membrane
mesangium
parietal layer of bowmans capsule
outer layer along basement membrane
inner layer of bowmans capsule
visceral
composed of podcytes
- spaces between endothelial cells: fenstra
- between foot processes: slit pores
basement membrane of bowmans capsule
prevents plasma proteins, RBC, WBS, and platlets from passing through
mesangium of bowmans capsule
mesangial cells and matrix
- contraction and relaxation -> affect GFR
- structural support
collecting tubule
multiple distal tubules empty into a single collecting duct, which merges with other ducts
- empty into minor calices through papilla
2 types of cells
- Principal (P) Cells
- Intercalated (I) cells
principal (P) cells
respond to ADH
- inc. ADH: more than 99% of filtrate reabsorbed
intercalated (I) cells
acid-base balance
- regulate secretion of acid
