B2.1.3 - Active Transport Flashcards
What does active transport allow?
Active transport allows cells to move substances from an area of low concentration to an area of high concentration
What must be transferred when the particles are moving, and from where?
Energy from an energy store
What are the three key features of active transport?
Particles are transported against a concentration gradient.
ATP is required - this comes from respiration
The process makes use of carrier proteins in the cell membrane
What do cells that do a lot of active transport have a lot of?
Mitochondria
How does having lots of mitochondria help active transport?
You can create more ATP
What does the rate of active transport depend on?
The rate of respiration to produce the required ATP
Where are carrier proteins located?
Along the width of the cell membrane
What are carrier proteins able to do?
Bind to a useful protein, rotate and place it inside the cell
How are carrier proteins able to rotate?
They use energy from energy stores
When is active transport used?
Whenever a substance needs to be moved against a concentration gradient
State how active transport is used in digestion
In your small intestine carbohydrates are broken down into glucose, which actively transports into the bloodstream through the villi
How is active transport used in nerve cells?
A carrier protein actively pumps sodium ions out of the cell. At the same time potassium ions are pumped back in. The sodium potassium pumps play an important role in creating nerve impulses
How do plants use active transport?
They use it to take in minerals from the soil
State an example of where a plant would need to use active transport.
Plants need nitrate ions to make proteins for growth. There is normally a lower concentration of nitrate ions in the soil water surrounding the roots than in the plant. The plant root hair cells use active transport to move these ions across the cell membrane and into the root hair cells
