Substances move from an area of LOW concentration to an area of high concentration across a permeable membrane
- Across a concentration gradient so requires energy from mitochondria
Root hair cells:
- Plants need mineral ions for healthy growth
- The concentration of minerals is usually higher in the root hair than in the soil
- Therefore root hair cells can’t use diffusion to take up minerals
Active transport happens in humans e.g. taking glucose from the gut and kidney tubules
- Lower concentration of nutrients in the gut to a higher concentration of nutrients in the blood
- Glucose, taken from the gut can be taken into the bloodstream and transported to cells to be used for respiration