The cell membrane's main trait is its selective permeability, which means that it allows some substances to cross it easily, but not others. Small molecules that are nonpolar (have no charge) can cross the membrane easily through diffusion, but ions (charged molecules) and larger molecules typically cannot.
Remove dead skin from hands and feet. The basic way to exfoliate hands and feet begins with keeping them in warm soapy water for at least 15 minutes. You will notice that your skin has become ultra soft. Now the time begins to exfoliate your hands and feet. Apply the scrub to skin and rub it for 15 minutes.
1 The skin on your feet is thicker, and to keep it soft and smooth itâs important to remove dead skin with exfoliation. 2  Massage the scrub in circular motions, and rinse off afterward. 3  To exfoliate the hardened skin on the heels and bottom part of the feet, use a foot file or a pumice stone. To exfoliate the hardened skin on the heels and bottom part of the feet, use a foot file or a pumice stone. 2  Make sure to use a gentle filing motion, and to never rub too hard. 3  If you have tough callouses, try a callous shaver to remove them from your heels and the sides of your toes.