Active Transport Flashcards
Active transport
the movement of particles against a concentration gradient (from an area of lower concentration to an area of higher concentration) using energy released during respiration
Example of where active transport is used
in the digestive system when there’s a low concentration of nutrients in the gut, but a high concentration of nutrients in the blood
What happens where there’s a higher concentration of nutrients in the gut?
they diffuse naturally into the blood
When is the concentration gradient the wrong way?
when there’s a lower concentration of nutrients in the gut than there is in the blood, but active transport allows nutrients to be taken into the blood even though the concentration gradient is the wrong way.
What are the 4 factors that affect the movement of substances?
surface area to volume ratio, distance, temperature and concentration gradient
How does surface area to volume ratio affect the movement of substances?
The rate of diffusion, osmosis and active transport is higher in cells (or cubes) with a larger surface area to volume ratio
The smaller cube has a large surface area to volume ratio which means substances would move into and out of the cube faster
How does distance affect the movement of substances?
If substances only have a short distance to move, then they’ll move in and out of cells faster
How does temperature affect the movement of substances?
As the particles in a substance get warmer they have more energy so they move faster which means as temperature increases, substances move in and out of cells faster
How does the concentration gradient affect the movement of substances?
Substances move in and out of a cell faster if there’s a big difference in concentration between the inside and outside of the cell.
Also concentration gradient only increases the rate of diffusion and osmosis and not active transport as it doesn’t affect it’s rate
