The need for transport in a plant

• Larger organisms do not have sufficient absorbing area to meet their needs, represented by their volume.
• The surface area of a cube 10 cm × 10 cm × 10 cm is 600 cm 2 and the volume is 1000 cm 3.
• Phloem is part of the close transport system.
• There aren't any perfect cube-shaped organisms, but the same principles apply to small and large ones.
• As the size of an organism increases, its surface area in relation to its volume decreases.
• Larger plants and animals need transport systems and to ensure that they have sufficient absorbing surface area.
• Xylem vessels are part of the close transport system.
• Larger plants and animals have two types of transport systems: close transport system A body system specialised to transport molecules and ions in multicelluar animals and plants and phloem The tissue in plants that transports the products of photosynthesis, including sugars and amino acids.
• The surface area:volume ratio of a cube 10 cm × 10 cm × 10 cm is 0.6:1.
• Xylem vessels are narrow, hollow, dead tubes with lignin, responsible for the transport of water and minerals in plants.
• Once inside a larger organism, a substance will also have further to travel to diffuse.
• The surface area:volume ratio of a cube 10 cm × 10 cm × 10 cm can be simplified to 0.6.
• Phloem consists of sieve tubes, companion cells, and phloem parenchyma cells.