Cellular Transport Flashcards
Passive Transport
movement of molecules across a cell membrane from a higher concentration to a lower concentration. NO additional energy.
Simple Diffusion
a process where a substance passes through a membrane without help from an intermediary. This is passive transport.
Facilitated Diffusion
a process where a substance passes through a membrane with an aid of a facilitator. The facilitator is a membrane proteins that spans the width of the membrane. The force that drives the molecule from one side of the membrane to the other is the force of diffusion.
Osmosis
the movement of water molecules through a semipermeable membrane from an area of high water concentration to an area of low water concentration (passive transport) Ex: plants use osmosis to take in water and minerals essential for its growth.
Active Transport
the movement’s molecules across a cell membrane from a lower concentration to a higher concentration. Additional energy is required.
Ion pumps
An ion pump is a trans membrane proteins that moves ions across the plasma membrane. The primary transporters are enzymes and convert energy from many sources like sunlight. Active transport. Examples: sodium potassium pump.
Contransport
two substances are transported simultaneously across a membrane by one protein, or protein complex which does not have ATPase activity.
Endocytosis
the taking in of matter by a living cell by invagination of its membrane to form a vacuole.
Phagocytosis
cell eating/ devouring
Pinocytosis
the ingestion of liquid into a cell by the budding of small vesicles from the cell membrane. Ex: human egg cells
Receptor mediated endocytosis
a way of bringing in specific molecules with receptors
Hypertonic
the concentration of the dissolved substances (solute) in the solution surrounding the cells is higher than the concentration of dissolved substances in the cell.
Hypotonic
the concentration of the dissolved substances in the solution surrounding the cell is lower than the concentration of dissolved substances in the cell.
Isotonic
the concentration of the dissolved substances in the solution surrounding the cell is the same (equal to) the concentration of dissolved substances in the cell.
