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9 Cards in this Set
- Front
- Back
What are the 4 functions of the peripheral circulation?
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1. Carries Blood -bloodflow to tissues
2. Exchange nutrients, waste, gas exchange 3. Transports substances : hormones, immune sys., enzymes 4. Helps regulate blood pressure |
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Describe continuous capillaries
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no gaps
less permeable to large molecules Has Basement membrane found in muscles, nervous and many other |
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Describe fenestrated capillaries
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found in intestinal villi, cilliary processes of the eye, choiroid plexuses of CNS, glomeruli (kidneys)
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What are sinusoids?
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large diameter sinusoidal capillaries with incomplete membrane, clefts and large fenestrations.
found in liver and bone marrow |
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How do substances diffuse through capillaries?
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1. between endothelial cells
2. through fenestrae 3. through the plasma membrane (simple diffusion) 4. Transcytosis (material moved right through a cell via endocytosis then exocytosis ) |
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What are venous sinuses?
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Vein with a thin endothelial wall with no smooth muscle to alter diameter. Surrounding dense connective tissue replaces tunica media and tunica externa.
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What type of molecules readily diffuse across the plasma membrane?
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Lipid soluable - through plasma membrane.
small water soluable - through intercellular crefts or fenestrations. |
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What are the three layers that make up the structure of arteries and veins?
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1. Tunica interna
2. tunica media 3. tunica externa |
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Describe the tunica interna
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Endothelium
Basement Membrane Internal Elastic Lamina |