Plant Exchange

• What is the pressure in the phloem of a plant?

  Around 2000 kPa
• What are the three main reasons that multicellular plants need transport systems?

  1. Metabolic Demands

  2. Size

  3. Surface Area to Volume ratio
• Why do plants need transport systems because of metabolic demands?

  Many internal or underground parts of a plant cannot make their own glucose for energy via photosynthesis, so need glucose and oxygen transported to them. Hormones and mineral ions also need to be moved.
• Why do mineral ions need to be moved around a plant?

  So they can be moved to all cells for protein production
• Why is the surface area to volume ratio not simple in plants?

  The leaves are adapted to have a large surface area to volume ratio, but when taking into account the stems, trunks and roots the overall SA:V ratio may be quite small