Transport in Plants 0.0 / 5 ? BiologyPlant Nutrition and TransportIGCSEEdexcel Created by: BethanyCreated on: 09-04-19 12:19 Section 3: Transport in Plants Cells in all living organsims need a variety of substances to live, e.g. water, minerals, sugars, and to remove waste substances In unicellular organisms, substances can diffuse directly into/out of cells across the membrane The diffusion rate is quick because the distance to travel is short In multicellular organisms, direct diffusion from outer surfaces would be too slow because the distance would be too long to reach every cell Multicellular organsims have transport systems to move substances quickly 1 of 3 Plant Transport Systems Plants have two systems to transport substances: Xylem tubes and Phloem tubes Xylem tubes transport water and minerals by carrying them from the roots up the shoot to the leaves in the transpiration stream Phloem tubes transport sugars and amino acids from the leaves to other parts of the plant This movement of "food" around the plant is known as translocation 2 of 3 PAPER 2: Root Hairs Cells on plant roots grow into long "hairs" which stick into the soil Each branch of a root is covered in millions of hairs, creating a large surface area to absorb water from the soil Water is taken in by osmosis: there's usually a higher concentration of water in soil than inside plant, so water is drawn into root hair cells 3 of 3
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