Membrane Barrier

Membrane Barrier Overview

Permeability

• The membrane barrier is differentially permeable.

  • Regulates the entry and exit of substances.

Mechanisms of Crossing (PA)

1. Passive Processes

   • No energy expended by the cell.

2. Active Mechanisms

   • Cell provides energy to translocate toxicants.

Determinants of Permeability

• Physicochemical properties influence permeability, including (MHP):

  • Molecular weight

  • Hydrophilicity

  • Polarity (total polar surface area)