Flashcards in Urinary System I & II Deck (79)
What two hormones does the kidney produce? What do they do?
erythropoietin - stimulated RBC production
Renin - influences blood pressure and the concentration of Na in body fluids
the renal hilum is continuous with what structure?
renal sinus (central cavity containing fat)
what is at the apex of each renal pyramid?
renal papilla with its perforated tip called the area cribrosa
where does the area cribosa project?
into the lumen of the minor calyx
what is a medullary ray?
group of straight tubules that project into cortex from the base of each renal pyramid
what makes up a renal lobe?
cotical tissue - medulla - cortical tissue
what makes up a renal lobule?
medullary ray (center) and surrounding cortical tissue
what are all nephrons in a single lobule drained by?
the same collecting tubules
what makes up the uriniferous tubule?
- originate from different embryologic structures
what are the two types of nephrons? What is their distinguishing features?
cortical - short loops of Henle
juxtamedullary - long loops of Henle (help kidneys form hypertonic urine)
- depends on location of the renal corpuscle
what makes up the renal corpuscle?
glomerulus (capillary tuft)
what kind of epithelium make up the parietal layer of Bowman's capsule?
simple squamous epithelium
what type of epithelium makes up the visceral layer of Bowman's capsule?
modified simple squamous epithelial layer investing the glomerular capillaries
what cells are found in the visceral layer of Bowman's capsule?
what are podocytes?
modified simple squamous epithelial cells that make up the visceral layer (glomerular epithelium)
have radiating processes - give rise to pedicles = foot processes
pedicles interdigitate with neighboring podocytes pedicles
what is found between adjacent pedicle filtration slits?
bridge of slit diaphragm (membrane)
where is the basal lamina located in the glomerulus?
between the podocytes and the endothelial cells in glomerulus
what are the 3 zones of the basal lamina in glomerulus?
lamina rara externa
lamina rara interna
what are characteristics of the endothelium?
thin and fenestrated lining capillaries = huge holes!
contains most organelles in thicker regions
what is the function of the filtration barrier? Where is it located?
functions to filter blood plasma
located in renal corpuscle
what does the filtration barrier allow to enter capsular space?
what defines what can pass through filtration barrier?
size, shape and charge of molecules - absolutely cannot be negative because everything else is negative!
where are interglomerular mesangial cells found? What is their function?
interstitial space of glomerulus between capillaries
clean up basal lamina
why do interglomerular mesangial cells contract?
to decrease surface area available for filtration
what do interglomerular mesangial cells have receptors for?
atrial naturitic factor
what is a feature of proximal convoluted tubule? what is its function of its apical and lateral borders?
well developed brush border = Mv
apical - protein absorption
lateral - water absorption
extensive basal plasma infoldings - ionic exchange!
where are 80% of NaCl and water and ALL the glucose, amino acids, and small proteins in glomerular filtrate absorbed?
proximal convoluted tubule
in the PCT, what are H+ secreted in exchange for?
Note - acids and bases also secreted here
where is the first place we see transitional epithelium?