Active Transport Flashcards
What is active transport
The movement of molecules or ions into or out of a cell from a region of lower concentration to a region of higher concentration using ATP and carrier proteins
What is ATP used for in active transport
Directly move molecules
Individually move molecules using a concentration gradient which has already been set up by active transport. This is known as co-transport.
How does active transport differ from passive forms of transport
Metabolic energy in the form of ATP is needed
Substances are moved against a concentration gradient, that is from a Lower to high concentration
Carrier protein molecules which act as pumps are involved
The process is very selective, with specific substances being transported
Describe the active transport of a single molecule
Carrier protein binds to molecule
Molecule binds to receptor sites on the carrier protein
ATP undergoes a hydrolysis reaction, splitting adp and p, this releases energy so that the solutes can be transported
The phosphate molecule is released from the protein which causes the protein to revert to its original shape, ready for the process to be repeated. The P then combines with ADP to form ATP during respiration
What happens in the sodium potassium pump
Sodium ions are actively removed from the cell while potassium ions are actively taken in form the surroundings. This process is essential to a number of processes in the organism
