Active Transport Flashcards
What is active transport?
When substances needed by a cell have to move against the concentration gradient across a partially permeable membrane.
Allows substances to move from area of low concentration to high concentration.
What is it useful for?
It allows cells to absorb ions from very dilute solutions
It enables cells to move sugars and ions from one place to another
How is the energy produced for active transport?
The energy is produced during cell respiration
The rate of respiration is linked to the rate of active transport as cell respires and releases a lot of energy it can carry out lots of active transport.
Active transport cells usually have lots of mitochondria to release energy
Examples of active transport cells
Root hair cells in plants
Cells lining the gut in animals
When is it important?
- Mineral ions eg Nitrate usually in very dilute solutions
More dilute than solutions within root hair cells.
Active transport absorbs ions against concentration gradient - Sugar eg glucose always actively transported out of gut and kidney tubules against concentration gradient. It is needed for respiration. When sugar is higher concentrated in blood than gut active transport balances it.
