DEFINITIONS+OF+NUTRITION+FUNCTION



** NUTRIENT is a chemical substance which can be used by cells to make or repair their structures and to obtain energy. E.g. carbohydrates, lipids, proteins, water, vitamins ** ** BREATHING is a process that moves air in and out of an organism. **
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** PAGE 22 ** ** [|ROOT HAIR CELLS] are structures located at the tips of the roots, whose cells absorb water and dissolved mineral salts from the soil. ** ** STOMATA are tiny pores located on the underside of leaves; gases enter and leave the plant through them ** ** RAW SAP is a liquid made up of water and mineral salts that is absorbed by the roots. ** ** XYLEM VESSELS take raw sap from the roots to the green parts. ** ** ELABORATED SAP is a thick liquid of water and __organic nutrients__ produced by photosynthesis. ** ** PHLOEM VESSELS distribute the elaborated sap from the leaves throughout the plant ** ||   || ** GASTROVASCULAR CAVITY. Bag shaped structure where digestion takes place. It has a single opening which serves as both mouth and anus. ** ** DIGESTIVE TRACT. Tube of varying length with one opening for food to go in and another for waste material to go out. ** ||  ||
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** PAGE 26 ** ** TRACHEAE are very thin internal tubes that lead out of the body through pores called spiracles and extend inside the animal where eventually branch out to the tissues. They carry air directly to the cells. ** ** LUNGS are two spongy organs which have very thin, damp walls full of blood vessels. They are formed by millions of minute cavities (alveoli) or air capillaries (in birds). **