Urinary System Flashcards
concave medial border where nerves enter, ureter exits and blood and lymph vessels enter and exit- lateral border is convex covered by a thin fibrous capsule
Hilum
upper expanded end of the ureter which divides into
Renal Pelvis
outer darker region with many corpuscle and cross section of tubules
Renal Cortex
inner layer consisting of 8-12 conical structures called renal pyramids which are separated by extensions the cortex called renal columns
Renal Medulla
each pyramid plus the cortical tissue at its base and along
Renal lobe
consist of the central medullary ray and the closely associated cortical tissue on either side of it, extending as far as in interlobular artery. Its many nephrons drain into the collecting tubules of the medullary ray
Renal Lobule
striations extending from the medulla into the cortex
Medullary Rays
tip of the renal papilla that projects into a minor calyx that collects urine formed by tubules in the pyramid
Renal papilla
Consists primarily of fibroblasts and mononuclear cells (probably macrophages).
Renal Interstitium
In the medulla, they are located along the blood vessels that supply the loops of Henle.
Pericytes
It is a vasodepressor hormone converted to medullipin II in the liver.
Medulllipin I
It is a vasodilator that acts to reduce blood pressure
Medullipin II
Nephrons can be classified according to location of the renal corpuscle:
NEAR THE CORTICOMEDULLARY JUNCTION
Juxtamedullary
Simple Squamous Epithelium lining Bowman capsule: Podocytes (visceral layer), outer (parietal layer)
Renal Corpuscle
Simple Cuboidal Epithelium with Brush border: many compartmentalized mitochondria
Proximal convoluted tubule
Simple Cuboidal Epithelium: compartmentalized mitochondria
Loop of Henle; ascending thick limb
Lined by simple cuboidal epithelium with brush border
Loop of Henle, descending thick limb
Simple Squamous Epithelium
Loop of Henle, descending thin limb
Simple Squamous Epithelium
Loop of Henle, ascending thin limb
Simple Cuboidal Epithelium
JG apparatus macula densa
JG cells in the afferent arteriole
Modified smooth muscle cells containing renin granules
Distal convoluted tubule
Simple cuboidal cells: compartmentalized mitochondria
Collecting tubules
Simple Cuboidal Epithelium; simple columnar epithelium
They possess longer loops of Henle than cortical or mid-cortical nephrons and are responsible for establishing the interstitial concentration gradient in the medulla.
Juxtamedullary nephrons
It consists of the glomerulus and Bowman capsule and is the structure in which the filtration of blood occurs.
Renal corpuscle
In a Bowman capsule:
It is the simple squamous epithelium that lines the outer wall of the Bowman capsule.
Parietal layer
In a Bowman capsule:
It is the modified simple squamous epithelium composed of podocytes that lines the inner wall of the Bowman capsule and envelops the glomerular capillaries.
Visceral layer (Glomerular epithelium)
In a Bowman capsule:
It is the narrow chalice shaped cavity between the visceral and parietal layers into which the ultrafiltrate passes.
Bowman space (also known as capsular space or urinary space)
In a Bowman capsule:
It is the site on Bowman capsule where the afferent glomerular arteriole enters and the efferent glomerular arteriole leaves the glomerulus.
Vascular pole
In a Bowman capsule:
It is the site on Bowman capsule where the capsular space becomes continuous with the lumen of the proximal convoluted tubule.
Urinary Pole
They are highly modified epithelial cells that form the visceral layer of Bowman capsule and synthesize glomerular endothelial growth factor, a signaling molecule that facilitates the formation and maintenance of the glomerular endothelial cells.
Podocytes
They have complex shapes and possess several primary processes that give rise to many secondary processes called pedicels.
Podocytes
It embraces the glomerular capillaries and interdigitate with pedicels arising from other primary processes.
Pedicels
Pedicels surfaces facing Bowman space are coated with a protein that is thought to assist in maintaining their organization and shape called:
Podocalyxin
Pedicels possess molecules that cause them to adhere to the basal lamina called:
α2β1integrin
They are elongated spaces about 40 nm in width between adjacent pedicels.
Filtration slits
It bridges each filtration slit and is the principal structure that is the barrier responsible for the filtration of proteins.
Filtration slit diaphragm
Each slit diaphragm comprises the extracellular portion of the transmembrane protein of one pedicel that contacts the extracellular portion of that protein from the adjacent pedicel.
Nephrin
It is the tuft of capillaries that extends into the Bowman capsule.
Renal Glomerulus
- It forms the inner layer of the capillary walls.
- have a thin cytoplasm thicker around the nucleus, where most organelles are located.
- possess large fenestrae (60-90 nm in diameter) but lack the thin diaphragms that typically span the openings in other fenestrated capillaries.
Glomerular endothelial cells
It is between the podocytes and the glomerular endothelial cells and is manufactured by both cell populations. It is unusually thick (0.15-0.5 um)
Basal Lamina
Three Distinct Zones of Basal Lamina:
It is an electron-lucent zone adjacent to the podocyte epithelium
Lamina rara externa