Term
| How do electrolytes, glucose and amino acids move across capillaries? |
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Definition
| diffusion through capillary pores |
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Term
| How does O2, CO2, fatty acids & hormones move across capillaries? |
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Definition
| diffusion through endothelial cells of capillaries |
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Term
| Why does the liver have very wide capillary pores/clefs? |
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Definition
| the liver produces plasma proteins, which need to be able to pass through these pores |
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Term
| Why is it important for the brain to have very small capillary clefts? |
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Definition
| to maintain the blood brain barrier |
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Term
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Definition
| Rate of diffusion = (Diffusion Coefficient X Concentration Gradient) / Distance |
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Term
| How does lipid solubility affect diffusion coefficient? Molecular size? |
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Definition
More soluble = greater diffusion coefficient
Smaller size = greater diffusion coefficient |
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Term
| Net osmotic pressure favors water movement (into/out of) capillaries |
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Definition
| into (favours water reabsorption) |
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Term
| Net hydrostatic pressure favours water movement (into/out of) capillaries |
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Definition
| out of (into interstitial fluid) |
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Term
| What would effect would an increase in hydrostatic pressure have on the tendency for water to filter from capillaries into the interstitium? |
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Definition
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Term
| What would effect would an increase in oncotic pressure difference have on the tendency for water to filter from capillaries into the interstitium? |
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Definition
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Term
| What would effect would an increase in water permeabilty of capillary endothelium have on the tendency for water to filter from capillaries into the interstitium? |
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Definition
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Term
| How does excess interstitial fluid get returned to the CV sytem? |
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Definition
| via lymphatics (subclavian veins feeding into the vena cava) |
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Term
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Definition
| water + protein collected from interstitium |
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Term
| How does lymph move throughout the lymphatic system? |
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Definition
Bulk Flow
-skeletal muscle contraction, lung expansion/contraction, one way valves & smooth muscle in vessels all move lymph around |
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Term
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Definition
-excess filtration of fluid from capillaries into interstitium
-loss of function of the lymphatic system |
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Term
| What is the correlation between venous pressure & edema? |
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Definition
| Increased venous pressure will increase capillary hydrostatic pressure, causing a buildup of fluid in the interstitium |
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Term
| Why might kidney failure or loss of GI absorption capacity lead to edema? |
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Definition
| protein-losing diseases like these can ead to hypoproteinemia, which leads to a loss of oncotic pressure. Fluid will be more inclined to move from capillaries into interstitium, leading to edema. |
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Term
| Why might liver failure lead to edema? |
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Definition
| loss of ability to produce proteins = lower oncotic pressure = fluid moves to interstitium |
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Term
| Pulmonary edema is often due to.... |
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Definition
| increased venous pressure leading to an increase in hydrostatic pressure |
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