Term
| What is the renal corpuscle? |
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Definition
| The renal corpuscle is the initial blood filtering unit of the nephron. It is made of the bowman's capsule and the glomerulus. |
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Term
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Definition
| The glomerulus is a group of capillaries in the bowman's capsule. |
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Term
| What tissue layers make up the renal corpuscle? |
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Definition
| The renal corpuscle is made up of the parietal (simple squamous epithelial cells) and visceral layer (podocytes) |
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Term
| If proliferation of simple squamous epithelial cells has occurred which layer of the renal corpuscle is this stemming from? |
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Definition
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Term
| What type of cells make up the proximal convoluted tubule? |
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Definition
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Term
| What cells secrete renin? What is the function of this? |
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Definition
| Juxtaglomerular cells secrete renin to maintain blood pressure. |
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Term
| What does the ultrafiltrate contain? What does it not contain? |
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Definition
| Ultrafiltrate contains water, solutes of blood. Ultrafiltrate does not contain proteins or blood cells. |
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Term
| What prevents large proteins from passing freely through the glomerular endothelium? |
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Definition
| Podocytes form filtration slits of about 25 nm which limits molecules on size. The pedicels are also covered with a glycoprotein that repels large negatively molecules. |
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Term
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Definition
| Excess protein in the urine. |
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Term
| Where are mesangial cells located? |
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Definition
| There are intraglomerular mesangial cells and extraglomerular mesangial cells which are located in the juxtaglomerular apparatus. |
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Term
| What cells have receptors for angiotensin II? What is the effect of angiotensin II on bp and glomerular blood flow? |
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Definition
| Intraglomerular mesangial cells have angiotensin II receptors and it causes contraction of glomerular capillaries which will decrease renal filtration and increase blood flow. |
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Term
| What substances does the proximal convoluted tubule reabsorb? |
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Definition
80% of water, Na, and Cl
100% glucose, amino acids, bicarbonate |
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Term
| What are some basal modifications of the proximal convoluted tubule? |
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Definition
-elongated mitochondria
-extensive basal infoldings of cell membrane |
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Term
| What are three substances secreted by the proximal convoluted tubule? |
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Definition
-creatine
-penicillin
-para-amino-hippuric acid |
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Term
| What is the name of the structure following the proximal convoluted tubule? What are some characteristics of this structure? |
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Definition
Loop of Henle
Has a thick and thin descending limb, then thin and thick ascending limb. |
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Term
| What types of cells make up the thick portions of the loop of henle? The thin portions? |
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Definition
Thick portions-cuboidal epithelium
Thin portions-squamous epithelium |
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Term
| What is the difference between a cortical nephron and a juxtamedullary nephron? |
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Definition
The location of the loop of henle differentiates cortical and juxtamedullary nephrons.
Cortical nephrons-loop of henle is located in the outer medulla.
Juxtamedullary nephrons the loop of henle is located deep in the medulla. |
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Term
| What portion of the nephron is for reabsorption of water? |
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Definition
| The proximal convoluted tubule and the descending thin limb of henle's loop. Collecting tubule in the presence of ADH. (check) |
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Term
| What is the function of the macula densa? Where is it located? |
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Definition
| The macula densa is formed from modified (columnar instead of cuboidal) cells of distal convoluted tubule. The macula densa senses the sodium concentration and volume of water in the distal convoluted tubule. If a decrease in Na concentration is detected then macula densa cells then stimulate the jg cells to release renin. |
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Term
| Secretion of what substance would inhibit renin secretion? Why? |
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Definition
| ANF inhibits renin secretion b/c they act oppositely. Renin is released in response to a decrease in NaCl concentration (lower BP). ANP is released by the atria in response to high bp. |
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Term
| Of the two types of the collecting tubule cells which is more common in the cortex? In the medulla? |
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Definition
Principal cells are more common in the medulla.
Intercallated cells are more common in the cortex |
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Term
| Which cells of the collecting tubules can ADH act on to promote water conservation? What is the mechanism for this? |
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Definition
| Principal cells of the CT have ADH aquaporin 2 water channels that open when ADH stimulates them. This allows for water to cross out of the lumen of the collecting tubule. |
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Term
| Which cells of the collecting tubule are responsible for proton secretion? |
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Definition
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Term
| What cells make up the juxtaglomerular apparatus? |
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Definition
-extraglomerular mesangial cells
-macula densa
-jg cells |
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Term
| What cells specialize into JG cells? |
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Definition
| Smooth muscle cells in the tunica media of the afferent arteriole. |
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Term
| What contractile cells contain actin--podocytes or mesangial cells? |
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Definition
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Term
| What type of collagen fibers are found within the lamina densa? |
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Definition
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Term
| What cells have receptors for atrial natruiretic factor? What is its effect on these cells? |
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Definition
| Intraglomerular mesangial cells--causes the mesangial cells to relax. |
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