-Each asexual organs. -Anchors the plant -Absorbs water and minerals -Stores sugars and starches

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Jasper Kelley
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1 Plants are made up of: -organs, tissues, and cells The three major plant organs are: -Roots, stems, and leaves -Each asexual organs Plants have a Root System beneath the ground that us a multicellular organ which: -Anchors the plant -Absorbs water and minerals -Stores sugars and starches Additional Root Structures: -At the tips of the roots vast number of tiny root hairs increase the surface area enormously, making efficient absorption of water and minerals possible -Plants may also have a symbiotic relationship with fungi and the tips of the roots, termed mycorrhizae (fungus root) -Mycorrhizae assist in the absorption process and are found in the vast majority of all plants

2 Plants have a Shoot System above the ground that works as a multicellular organ -Leaves are the main photosynthetic organ inmost plants -Stems function primarily to display the leaves Plant organs-leaf, stem, and root- are composed of three tissues types: -Dermal tissue -Vascular tissue -Ground tissue Dermal Tissue -Is a single layer of closely packed cells that cover the entire plant and protect it against water loss (cuticle) and invasions by pathogens like viruses and bacteria Vascular Tissue -Is continuous through the plant an transports materials between the roots and shoots -Is made up of xylem, which transports water and minerals up from the roots and phloem, which transports food from the leaves to the other parts of the plant -Xylem cells have two types of water conduction cells: tracheids and vessels that are dead at functional maturity -Phloem cells conduct sugar and other organic compounds. Phloem is composed of two types of cells, sieve tubes and companion cells, both alive at maturity

3 Ground Tissue -Is anything that isn t dermal tissue or vascular tissue -Used for storage and photosynthesis Plant Growth -For growth, plants have meristems that generate cells for new organs -Meristems are perpetual embryonic tissue that are responsible for indeterminate growth (growth throughout the plant s life) Plant Meristems: -Perpetual embryonic regions -Zones for cell division Two Types of Plant Meristems -Apical Meristems are located at the tips of the roots and in the buds of shoots -These are the sites of cell division, allowing the plant to grow in length, Primary growth occurs when the plant grows at the apical meristems (length) -Lateral Meristems result in the growth which widens or thickens the shoot and roots, this is termed secondary growth Leaf Anatomy -Stem outgrows for Ps -Blade: the flattened portion of a leaf -Peptiole: stalk of a leaf Tissues within a Leaf: -Upper Epidermis -Mesophyll -Lower Epidermis -Veins

4 Upper Epidermis -Cuticle present -Usually one cell layer thick -Cells tightly packed together, have stoma, guard cell with chloroplasts -Function: Protects the mesophyll Mesophyll -Palisade: upright cells (Ps) -Spongy: loosely organized cells with air spaces (Gas Exchange) -Function: Major sites for Ps Lower Epidermis -No cuticle present -Usually one cell layer thick -Cells tightly packed together -Function: Many stomata, guard cells present for gas exchange Stomata -Regulated by guard cells which have chloroplasts

5 Veins -Xylem: transport water -Phloem: transport sugar -Veins located in mesophyll and are often surrounded by bundle sheath cells for support

Forms strands that conduct water, minerals, and organic compounds. Much of the inside of nonwoody parts of plants. Includes roots, stems, and leaves

Biology II Vascular plants have 3 tissue systems: Dermal Protective outer layer of plant Vascular Forms strands that conduct water, minerals, and organic compounds Ground Much of the inside of nonwoody