i) Thickness of membranes and tissues: The thicker the membrane or tissue, the lower the rate of diffusion. This is because the distance to be covered by diffusing molecules is greater. However if the membrane is thin, the rate of diffusion is high.
ii) Size of molecules: small and light molecules diffuse faster than large and heavy molecules.
iii) Temperature: An increase in temperature increases the energy content of molecules and causes them to move faster. An increase in temperature therefore increases the rate of diffusion while a decrease in temperature decreases rate of diffusion.
iv) Surface area of the of the volume ratio
v) Concentration gradient/ diffusion gradient
johnmulu answered the question on April 29, 2017 at 06:00
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In an investigation, a student extracted three pars of pawpaw cylinders using a cork borer. The cylinders were cut back to 50mm lenth and placed in a beaker containing a solution. The results after 40 minutes were as shown in the table below.
(Solved)
In an investigation, a student extracted three pars of pawpaw cylinders using a cork borer. The cylinders were cut back to 50mm lenth and placed in a beaker containing a solution. The results after 40 minutes were as shown in the table below.

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Date posted:
April 29, 2017
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Answers (1)
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Date posted:
April 29, 2017
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April 29, 2017
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Date posted:
April 28, 2017
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(Solved)
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Date posted:
April 28, 2017
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April 28, 2017
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April 28, 2017
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(Solved)
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Date posted:
April 28, 2017
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Answers (1)
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(Solved)
The figure below is a fine structure of a generalized animal cell as seen under an electron microscope.

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Date posted:
April 28, 2017
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Answers (1)
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Date posted:
April 28, 2017
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April 27, 2017
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April 27, 2017
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Date posted:
April 27, 2017
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Date posted:
April 27, 2017
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Date posted:
April 27, 2017
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Date posted:
January 21, 2017
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Date posted:
January 21, 2017
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January 21, 2017
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January 21, 2017
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January 21, 2017
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