Transport across Membranes Flashcards
The term used to describe the membrane because it only allows some molecules to pass through but not others.
Selectively Permeable
The components of the plasma membrane
Protein and Phosophlipids
Diffusion is
The movement of molecules from a high concentration to a low concentration
Osmosis is
The movement of water molecules from a higher water concentration to a lower water concentration, through a selectively permeable membrane
A passive process
Does not require energy (eg diffusion and osmosis)
Examples of diffusion
Oxygen and glucose diffuse IN to the cell. Carbon Dioxide and urea diffuse OUT of the cell.
Active transport is
The movement of molecules or ions from a low concentration to a high concentration
A plant cell that has gained water by osmosis is said to be
Turgid
A plant cell that has lost water by osmosis is said to be
Plasmolysed
An animal cell that has gained water by osmosis will
Burst
An animal cell that has lost water by osmosis will
Shrink
Plant cells will not burst because
They have a cell wall
An active process requires
Energy
