Transport Across Membranes-unit 1 Flashcards
Term used to refer to a structure that does not allow molecules in solution to pass through it
Selectively (semi-) permeable membrane
Term used to describe a structure (e.g plant cell wall) that allows all molecules in a solution to pass through it
Freely permeable
Movement of water molecules along a concentration gradient from a region of higher water concentration to a region of lower water concentration through a selectively permeable membrane
Osmosis
Région to which net movement of water molecules occurs during osmosis
Lower water concentration
Term used to describe plant cell whose contents have shrunk due to loss of water by osmosis
Plasmolysed
Term used to describe a plant cell swollen with water taken in by osmosis
Turgid
Movement of molecules of a substance from a region of higher concentration to an area of lower concentration until concentration is equal
Diffusion
Model of cell membrane showing a phospholipid bilayer embedded with proteins
Fluid mosaic modle
Movement of molecules of a substance from an area of lower concentration to an area of higher concentration which requires energy and a carrier protein
Active transport
Difference in concentration that exists between two regions resulting in diffusion
Concentration gradient
Structure that allows small molecules (e.g water) but not larger molecules to pass through it
Impermeable
Energy molecule produced during respiration required for active transport to occur
ATP
Region from which net movement of water molecules occurs during osmosis
Higher water concentration
