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Non-vascular Seedless vascular Seeded vascular
No conducting (vascular) tissue Usually small, grows close to the ground Must be found in moist environments Bryophytes such as mosses and liverworts
Vascular tissue well-developed No seeds produced Ferns, club mosses, horsetails
Seeds contain an embryo with nutrients and protective outer coat
Vascular tissue is extensive Most plants we know are in this category 2 categories-▪ Gymnosperms▪ Angiosperms▪ Monocotyledons▪ Dicotyledons
Two types of systems: Root System Shoot System: stem, leaf, flower
Plant organs: root, stem, leaf, flower referred to as plant parts
Anchorage Keeps plant in the soil Prevents soil erosion Holds stem in place
Absorption water dissolved minerals
Storage Starch Other nutrients
http://www.bio.miami.edu/dana/pix/taproot_fibrousroot.jpg
http://tchefty.wikispaces.com/file/view/rootsystems1.jpg/260637884/rootsystems1.jpg
http://kentsimmons.uwinnipeg.ca/2153/rootsystems1.jpg
Large long primary root Penetrate deep into the ground Small thin roots grow laterally off main root Strong anchoring system Examples: evergreen trees
Specialized to store water, food, nutrients
Better chance at drought survival
Examples: carrot, beet, turnip, radish
http://www.ontarioweeds.com/media/jpg/tropr_root.jpg
Many small roots that branch Increases surface area Better absorption of water and
minerals Less structural support Examples: peas, beans, lettuce
Small fibrous objects that branch off roots
Absorbs water and minerals
Zone of maturation: cells differentiate into different types of cells
Zone of elongation: allows the root to get deeper within the soil
Meristematic region: rapid mitosis of undifferentiated meristematic cells
Root cap: protects the meristematic region
Cells in the root have no chloroplasts and are not exposed to sunlight so they can not undergo photosynthesis to make their own food
Root cells must perform cellular respiration to obtain cellular energy
Glucose + oxygen carbon dioxide + water + energy
Glucose comes from the starch stored in the root Oxygen is absorbed through the soil
Stem Leaf Flower
Raises and supports branches, leaves and flowers
Transport of water and nutrients
In trees the main stem is the tree trunk
http://www.pxleyes.com/images/contests/bw%20tree%20trunks/fullsize/bw%20tree%20trunks_4b6283790291c.jpg
Young green stems can perform photosynthesis because they have chloroplast in their epidermal cells
Some are specialized for food storage Examples: sugar cane, potatoes
http://upload.wikimedia.org/wikipedia/commons/9/96/Sugar_Cane.jpg
Main function: Photosynthesis Parts of the Leaf:
Cuticle Epidermis Guard Cells & Stoma Palisade cells Spongy Layer Vascular Tissue
Outer layer of cells
Leaf epidermis produces cuticle
http://www.goldiesroom.org/Multimedia/Bio_Images/05%20Nutrition/15a%20Cross%20Section%20of%20a%20Leaf.jpg
Waxy substance that coats the exterior
Water proofing Protect interior
tissues Blocks passage
of gases
http://www.goldiesroom.org/Multimedia/Bio_Images/05%20Nutrition/15a%20Cross%20Section%20of%20a%20Leaf.jpg
Stoma (Greek for “mouth”) Pore-like openings in the
plant’s epidermis Opening size controlled by
two guard cells permits gas exchange
between the leaf’s interior and external environment.
larger opening, faster gas exchange
Where water is stored
Where the vascular tissues reside
Contains many chloroplast for photosynthesis
Cells stand tall and upright Top end exposed
to light Bottom end
exposed to the gases in the spongy layer
Scanning electron microscope image of a leaf from a Black Walnut tree. (Dartmouth Electron Microscope Facility/Dartmouth College)
http://cache.boston.com/universal/site_graphics/blogs/bigpicture/micro_11_14/m04_walnut_leaf.jpg
Dermal Tissue Vascular Tissue Ground Tissue
Outermost layer of a plant Epidermis: thin layer of cells that covers the
surface of leaf, stem and root Periderm tissue: bark on stem and large roots
of woody plants (replaces the epidermis)
Some dermal tissues have unique functions Root cells: root hairs (long extensions) Leaf cells: produce cuticle
Plant circulatory system Vessels that connect roots to leaves Transports water, dissolved minerals, and
sugars throughout plant, providing cells with materials to carry out life functions
Two types: Xylem Phloem
made up of long hollow tubes formed by non-living cell walls (left over from plant cells that have died)
transports water and dissolved minerals upwards from roots
Made up of elongated cells that are living Transports:
solutions of sugars (food) Dissolved nutrients Hormones
Bi-directional movement of materials downward to roots upward to leaves
