Active transport Flashcards
What is the definition of active transport?
Active transport is the movement of ions and molecules through a cell membrane from a lower concentration of the ions/molecules to a higher concentration of the ions/molecules_(i.e. against a concentration gradient).
Why does the process active transport require protein carrier molecules?
This process uses protein carrier molecules in the membrane to transfer specific ions/molecules across the cell membrane.
Why does active transport require energy?
Active transport requires energy (from ATP) because it moves ions/molecules against a concentration gradient.
Describe the sodium/potassium pump.
The sodium/potassium pump is an example of a carrier molecule that pumps sodium ions out of the nerve cell and potassium ions into a nerve cell against their concentration gradients. This is how the nerve impulse is generated in a nerve cell.
