100 likes | 234 Views
Chapter #19. The Importance of Leaves. Chapter 19.1 Notes. Blade- thin, flat part of leaf. Stalk-usually joins the leaf to the stem. Midrib-is the main vein of the leaf. Blade. Midrib. Stalk. Leaves are arranged in 3 different ways. Alternate Opposite Whorled. Alternate. Opposite.
E N D
Chapter #19 The Importance of Leaves
Chapter 19.1 Notes • Blade- thin, flat part of leaf. • Stalk-usually joins the leaf to the stem. • Midrib-is the main vein of the leaf. Blade Midrib Stalk
Leaves are arranged in 3 different ways. • Alternate • Opposite • Whorled Alternate Opposite Whorled
Waxy layer- protective layer, protects from water loss & insects. • Epidermis-is the outer layer of cells of a plant. • Palisade layer- the layer of long, green cells below the upper epidermis (makes most of food). • Spongy layer- below palisade layer is a layer of round, green cells. Has air spaces. • Stoma- is a small pore or opening in the epidermis allows air and water to go in and out. • Guard cells- are green cells that change the size of stoma in a leaf. Found on either side of stoma.
Leaf Cross Section Waxy layer Epidermis Palisade Layer Spongy Layer Stoma Epidermis Guard cells
Transpiration- the process of water passing out through the stomata of leaves. • Wilting- is when a plant loses water faster than it can be replaced.
Chapter 19.2 Notes • Photosynthesis- is the process in which plants use water, carbon dioxide, and energy from the sun to make food • 6 CO2 + 6H2O C6H12O6 + 6O2 • Carbon dioxide + water = sugar + oxygen Sunlight Final Product Waste Product Raw materials
Chapter 19.3 Notes Food chain- always start with the sun…then a producer (green plant) Leaves are used for food, flavorings, spices, and making drugs… Digitals-drug used to treat heart disease.
Common pigments colors in leaves • Red • Yellow • Green • Why do leaves change color? • Flow of sap in the stem slows down • Temperature drops • Less sunlight • Chlorophyll breaks down • Other pigments show through
“Food Chain”. December 12, 2006. http://salina-int.dearbornschools.org/COATT/foodchain2.JPG • “Alder Leaf”. December 11,2006. http://www.schoolsliaison.org.uk/woodgate/leaves/alder1.jpg • “Leaf arrangement pictures (3)”. December 11, 2006. http://www.amnh.org/learn/biodiversity_counts/ident_help/Parts_Plants/plants_GIF_Files/3leaf_node.gif • “Leaf cross section”. December 12, 2006. http://www.bbc.co.uk/schools/gcsebitesize/img/bi05004.gif • “Maple Leaves in Fall”. December 12, 2006. http://tapestry.typepad.com/a_mingling_of_threads/Maple%20leaves.jpg