active transport

• active transport

  the movement of ions or molecules across a cell membrane into a region of higher concentration, assisted by enzymes and requiring energy.
• why are root hair cells specialised for active transport?

  - millions of microscopic hair, large surface area

  - many mitochondria to provide energy for the active transport
• Active transport in the gut

  - Substances such as glucose and amino acids from your food have to move from your gut

  into your bloodstream

  - Sometimes there can be a lower concentration of sugar molecules in the gut than the

  blood, meaning diffusion cannot take place

  - Active transport is required to move the sugar to the blood against its concentration

  gradient