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Tissue. an integrated group of cells with a common structure and function. Plant tissues. Meristematic tissue : rapid cell division, lengthening of shoots and roots Dermal tissue : covering for the plant body Ground tissue : support, photosynthesis, and storage
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Tissue an integrated group of cells with a common structure and function
Plant tissues • Meristematic tissue: rapid cell division, lengthening of shoots and roots • Dermal tissue: covering for the plant body • Ground tissue: support, photosynthesis, and storage • Vascular tissue: conduction of water, food, and dissolved minerals; strengthens and supports the plant
Apical meristem Region of cell differentiation/maturation • In shoot tips and root tips • Alliumcepa root tip Region of cell elongation Region of cell division Apical meristem Root cap
Dermal Tissue • Single layer of cells called the epidermis in herbaceous plants • guard cells • trichomes • root hairs • Functions • absorption • secretion of cuticle • protection • control of gas exchange Epidermis Cuticle
Vascular Tissue • Xylem • Conducts water and dissolved minerals from the roots • Phloem • Conducts dissolved food materials, carbohydrates, in solution • Continuous throughout plant • Support plant body
Young monocot stem Young dicot stem
Epithelial Tissue(Covering) • Tightly-joined closely-packed cells • One side of exposed to air or internal fluid, other side attached to a basement membrane • Covers outside of the body; lines internal organs and cavities • Barrier against mechanical injury, invasive microorganisms, fluid loss • Provides surface for absorption, excretion and transport of molecules
Types of Epithelial Tissue • Cell shape • Squamous • Cuboidal • Columnar • Number of cell layers • Simple • Pseudostratified • Stratified • RELATE STRUCTURE TO FUNCTION!
Binding and support of other tissues • Large amount of extracellular matrix with fewer cells • ECM - network of fibers in liquid, jelly-like or solid matrix
Muscle Tissue(Movement) • Composed of long cells called muscle fibers • Contraction movement
Nervous tissue(Control) • Senses stimuli and transmits nerve impulses • Single cell body with long extensions (axons and dendrites) Axon Dendrite Cell body