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# 1 cm2 001 cm 4 10 7 cm3o2s c if animal tissues

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Unformatted text preview: rates and lower oxygen demands (b) The oxygen concentration in its tissues is 5 ml/l . The oxygen concentration is 10 ml/l in the environment 0.1 mm from its surface (the diffusion distance for O2 to this animal). The diffusion constant for oxygen in water is 2x10- 5 cm2/s. One liter is 1000 cm3. How many ml of oxygen can this creature acquire by diffusion in every second? (6 pts) Use Fick’s Law : = [2 10- 5 cm2/s] [5 cm3 O2/1000 cm3] [4 π( 0.1 cm)2]/ [0.01 cm] = 4 π 10- 7 cm3O2/s (c) If animal tissues all have a density of 1 g/ml, how much oxygen per gram of tissue is delivered every second (4 pts) ? = [4 π 10- 7 cm3O2/s] / [ 4 π r3/3] = 3 10- 4 cm3O2/g s (d) If the creature were to double in radius, would the oxygen delivery increase by a factor or 2, 4, 6, or 8? In one sentence, explain your answer. (4 pts) A factor of 4 since the surface area rises by that factor. (d) If the creature were to double in radius, would the oxygen delivery per gram of tissue increase or decrease? In one sentence, explain your answer. (4 pts) It will decrease since the surface to volume ratio decreases as 1/r 2 Name (print)___________________________________ TA’s name________________ Last First 2. We have found a cell whose ion concentrations are as follows K+inside = 150 mM K+outside = 15 mM VK=____- 61mv_______ Na+inside = 10 mM Na+ outside = 100 mM VNa= __61mv_________ Cl- inside = 50 mM Cl- outside =...
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## This note was uploaded on 02/11/2013 for the course BIO 220 taught by Professor Unsure during the Winter '04 term at University of Washington.

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