Once inside a cell glycerol molecules have a diffusion coefficientof about 2.1x10^-10 m^2/s. Approximately how long would it takemolecules to diffuse from the membrane to the center of the cell,which is a biconcave disc about 10micrometers in diameter and about1 micrometer thick in the center.

a) if they entered at the periphery
b) if they entered at the centre

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