Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download LEAF
Document related concepts
Transcript
LEAF Nature’s Solar Panel LEAF Leaf stalk Petiole Leaf lacking petiole Leaf blade Lamina Appendages at base of petiole Sessile Stipules Network of veins Vascular bundles ARRANGEMENT Alternate One leaf per node Alternating along stem Opposite Most common Two leaves attached to a node Whorled Three or more attached to node SIMPLE LEAF One blade on petiole COMPOUND LEAF Multiple leaflets on petiole Pinnately compound Leaflets attached to extended petiole Rachis Bipinnately compound Multiple rachis COMPOUND LEAF Multiple leaflets on petiole Palmately compound All leaflets attached to end of petiole Palm VEINS Netted vein arrangement Parallel vein arrangement Dicots (broadleaves) Monocots (grasses) Only tree to have fan arrangement Ginkgo PHOTOSYNTHESIS Capture light energy Building blocks Water Carbon dioxide Energy in form of carbohydrates STOMATA Openings on lower surface of leaf Stomata Guard cells open and close Regulated by potassium (K) Inflated guard cells open Deflated guard cells closed STOMATA Gas exchange Carbon dioxide in Oxygen out Transpiration Water vapor evaporation Cooling plant Anti-Transpirant Reduce water loss Winter burn Christmas trees Transporting trees RESPIRATION Consumption of carbohydrates Growth EPIDERMIS Outer layer of cells Epidermis Waxy cutin Cuticle Thicker in the presence of pollutants or pests Epidermis on top and bottom of leaf Stomata mostly on bottom MESOPHYLL Cells between upper and lower epidermal layers Parenchyma cells with cholorplasts Cholorenchyma MESOPHYLL Upper mesophyll Palisade mesophyll Two rows Compacted barrel-shaped chlorenchyma cells Majority of photosynthesis MESOPHYLL Lower mesophyll Spongy mesophyll Loose arranged Abundant air spaces Primarily for gas exchange VEINS Vascular bundles Xylem Phloem Contained in a thick wall of parenchyma cells Bundle sheath SPECIALIZED LEAVES Shade leaves Lower part of tree Understory Larger Thinner Less sunlight and heat SPECIALIZED LEAVES Arid leaves Thicker Fewer stomata Reduce transpiration SPECIALIZED LEAVES Tendrils Whiplike strands sensitive to contact Wrap around object Thigmotropism Climbing vines In some cases, tendrils are stems Grapevine SPECIALIZED LEAVES Spines Cactus spines are modified leaves Tree spines are modified stipules Short paired spines Thorns Sclerenchyma cells Modified stems Prickles Outgrowth from stem epidermis Rose and raspberries SPECIALIZED LEAVES Storage leaves Water storage Succulents Large non-photosynthetic parenchyma cells Large vacuoles store water SPECIALIZED LEAVES Storage leaves Carbohydrate storage Onion and other bulbs Rapid growth early in season SPECIALIZED LEAVES Reproductive leaves Miniature plants on marge of leaf Kalanchoe SPECIALIZED LEAVES Floral leaves Bracts Colorful modified leaves at base of flowers Poinsettia SPECIALIZED LEAVES Carnivorous Over 200 species Bogs Nutrient deficient Acidic Wet SPECIALIZED LEAVES Pitcher Plant Hollow leaves that often collect water Waxy interior with downward pointing hairs Difficult to escape Wetting agents make it difficult to swim Digested by enzymes SPECIALIZED LEAVES Sundews Sticky fluid at the end of each hair follicle Digestive enzymes Hair bend inward upon contact of insect Can distinguish difference between protein object and inedible debris SPECIALIZED LEAVES Venus flytrap Native to lower NC and upper SC Trigger hairs in foliar trap Close on insects instead of debris Touched a few times within seconds Trap reopens after digestion SPECIALIZED LEAVES Bladderwort Submerged bladder leaves Trigger hairs outside a trap door Door opens and water rushes in along with aquatic insect AUTUMN COLOR Chlorophyll in greatest supply Breaks down first Shorter day length and cooler temperatures No longer masks other pigments Anthocyanin in vacuole AUTUMN COLOR Other pigments can be stored in vacuole Anthocyanin Red if sap is acidic Blue if sap is basic Betacyanins red ABSCISSION Process of dropping leaves Evergreen plants Abscission Gradually shed leaves Deciduous plants Shed leaves in winter https://www.youtube.com/watch?v=aladpRIVdRI
