LEAVES The organ of photosynthesis Contain chloroplasts/ chlorophyll Absorb light for photosynthesis

CUTICLE waxy layer to prevent water loss Deciduous trees: lose leaves in winter to prevent water loss & therefore freezing Evergreens: in tropical areas and polar climates (needle-like leaves to reduce water loss)

EPIDERMIS Protective layer of cells at top and bottom of leaf

STOMATA Openings in leaf that allow gas exchange and water release GUARD CELLS surround stomata and open or close the stomata

TRANSPIRATION Water loss by plants Increases in hot, dry environments Increases with leaf surface area Broader leaves lose more water; narrow leaves lose less water

Vascular Tissue XYLEM: transports water up a plant PHLOEM: transports food (sugars) up or down a plant

MESOPHYLL MESOPHYLL: area where photosynthesis takes place Contains chloroplasts Spongy and palisade layers Allows plants to manufacture carbohydrates (food) using sunlight

OBTAINING ENERGY AUTOTROPH HETEROTROPH (“self-feeding”) Have the ability to make its own food (using energy from the sun) EX: Plants (“different feeding”) Must obtain energy from feeding from other organisms Cannot make its own food EX: animals

PLANTS ARE EITHER VASCULAR NON-VASCULAR Contain vascular tissue (xylem & phloem) Most produce seeds Do not have vascular tissue (no xylem or phloem) Low-growing (to absorb water & nutrients from soil) Moist habitats EX: mosses & liverworts

VASCULAR PLANTS SEED PRODUCING NON-SEED PRODUCING Reproduce by producing seeds Do not produce seeds Reproduce by spore

SEED-PRODUCING PLANTS GYMNOSPERM “naked seed” Produce seeds in cones: referred to as CONIFERS Pine trees, hemlock, fir, spruce, cedar ANGIOSPERM “ VESSEL SEED” Produce seeds in flowers/fruit Flowering plants, DECIDUOUS TREES (trees that shed leaves: oak, hickory, maple