BIOL 1902 Lecture Notes - Lecture 6: Symphyotrichum Novae-Angliae, Aposematism, Potato
7 Apr 2016
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Plants face all the same problems that animals encounter, including the risk of being eaten. Plants face many animals that eat plants. All parts of a plant can be eaten by animals (pedals, steams, wood) Beetle grubs eat the wood when they hatch. Trees and other woody plants have external armour: bark. Seeds can be protected: nuts are seeds with armour. Some plants have sharp defensive structures: spines, thorns, prickles and thistles (all different) Spines: are modified leaves (can be long and pointy of just the edge of the leaf) Prickles: epidermal outgrowths, usually on the stem: ex. Roses: rose buds resemble prickles (possible mimicry: automimicry, ex. Structural elements such as cellulose, hemicellulose, and pectin make plant tissues hard to digest. Lignin (a structural component) gives leaves stiffness, nuts and cherry pits their hardness. Structural elements are digestible reducers (make it hard to digest) Horsetails have silica found in them (silica housed in phytoliths)
