BIO 446L 1st Edition Lecture 30 Outline of Last Lecture I. ReviewOutline of Current Lecture I. Urinary Systema. Anatomyb. Nephroni. Corticleii. Juxtameduklaryc. Blood flow through kidneysd. nephroni. Renal corpuscleii. Glomerular filtrationiii. Proximal convoluted tubuleiv. Loop of Henlev. Distal convoluted tubulevi. Collecting tubules and ductsvii. Ureters, bladder, and urethraCurrent Lecture- Urinary Systemo Kidney filters 180 L plasma—entire blood volume 60 times a dayThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- Anatomyo Retroperitonealo Renal artery—off of aortao Renal vein—off of inferior vena cavao ureters Brings filtrate to be excreted Exits through urethrao Kidneys Functional unit= the nephron- More on this later secrete erythropoietin and regulate pH Fibrous capsule- Made up of connective tissue Outer layer= cortex Inner layer= medulla- Renal columns- corticle tissue, divides medulla, blood vessels extend here and into cotex- Renal pyramids- made up of renal lobe= pyramid, columns of pyramid, and part of cortex in which vessels extend into- Nephrono Blood vessels tubules and capillarieso Filter, reabsorb, recreate, and excrete Filter= plasma out of blood into Bowman’s capsule Reabsorb= filtrate out of tubules into blood Secrete= cells lining tubules transport substances from blood into filtrate of tubules Excrete= what’s left over after filtration, reabsorption, and secretion leaves the body via uretersbladder urethrao Tubule system starts in Bowman’s capsule of renal corpuscle Bowman’s capsule—filtrate proximal convolutes tubule proximal straight tubule in medulla loop of Henle (wall thins) distal convolutedtubule in cortex (wall thickens again, makes contact with macula densa of corpuscle) collecting tubule collecting ducto Cortile nephron= tubules primarily in cortex along with corpuscleo Juxtamedullary nephron= corpuscle in cortex, tubules deep into medulla- Blood flow through the kidneyso Renal artery afferent arteriole glomerular capillaries efferent arteriole peritubular capillarie (portal system)o Capillaries surround the nephrono Kidneys receive 20-25% of cardiac output blood to be filtered- Renal corpuscleo Wall of Bowman’s is simple squamous epitheliumo Branch into glomerular capillaries Have visceral layer, surrounded by podocytes Podocytes—pedicels= projections from filtration slits (blood plasma Bowman’s)- -->fenestrated capillary endothelial to filtration slits to convoluted proximal tubuleo Juxtaglomerular apparatus Juxtaglomerular cells, macula densa, distal tube (between afferent and efferent arteriole)- Glomerular filtration membraneo Blood pressure moves filtrateo About 25 mL/min filtered across membraneo Filtration membrane Fenestrated epithelia of capillary on basement membrane, podocytes with filtration slits (with diaphragm to open and close) on basement membrane (fused)- Composed of type IV collagen, laminin, fibronectin, glycoproteins, GAGso Glycoproteins and GAGs are negatively charged Restrict large anionic proteins from crossingo Lets in ions, amino acids, glucose, vitaminso Does not let in RBCs, proteins, bacteria- Proximal convoluted tubuleo Most filtrate from Bowman’s gets reabsorbed in proximal convoluted tubuleo Tall microvilli (many more than distal)o Cuboidal, highly absorptive (microvilli, interdigitations, mitochondria)o Thicker wall than distalo Absorptive cell—lines capillaries has lots of mitochondria, vesicles, basal later Lots of mitochondria because lots of active transport requires lots of
View Full Document
Unlocking...