GENERAL HISTOLOGY

Detailed explanation-1: -Cell membrane The cell membrane encloses the cell. It acts like a gatekeeper-allowing some materials to pass through it, but not others.

Detailed explanation-2: -What Do Membranes Do? Cell membranes serve as barriers and gatekeepers. They are semi-permeable, which means that some molecules can diffuse across the lipid bilayer but others cannot. Small hydrophobic molecules and gases like oxygen and carbon dioxide cross membranes rapidly.

Detailed explanation-3: -Plasma membranes must allow certain substances to enter and leave a cell, while preventing harmful material from entering and essential material from leaving. In other words, plasma membranes are selectively permeable-they allow some substances through but not others.

Detailed explanation-4: -Cell Membrane (Plasma Membrane) The cell membrane consists of a lipid bilayer that is semipermeable. The cell membrane regulates the transport of materials entering and exiting the cell.