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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