active transport

• Root hair cells take in minerals and water - each branch of a root will be covered in millions of microscopic hairs. This gives the plant a large surface area for absorbing water and mineral ions from the soil. Plants need these mineral ions for a healthy growth. The concentration of minerals is usually higher in the root hair cell than in the soil around them.
• Minerals should move out of the root hairs if they followed diffusion, the cells must drag them in. This is active transport. Active transport allows the plant to absorb minerals from a diluted solution, against a concentration gradient but it needs energy from respiration to work.
• Active transport is used in the gut when there is low concentration of nutrients in the gut, but a high concentration of nutrients in the blood. When there is a high concentration of glucose and amino acids in the gut they diffuse into the blood but sometimes there's a lower concentration of nutrients in the gut than there is in the blood. This means that the concentration is the wrong way. Active transport allows nutrients to be taken into the blood, despite the fact that the concentration gradient is different. It can then be transported into the blood stream ready for respiration.