Unit 3

• All cells must


  Receive nutrients, exchange gases, and remove wastes
• Unicellular Organisms have


  All life processes occur in a single cell, Large surface area to volume ration, Short life
• Multicellular Organisms contain


  Specialized cells that preform special functions and have a longer life
• Plant Organ systems


  shoot system and root system
• Shoot systems


  The aerial portion of a plant body, consisting of stems, leaves, and (in angiosperms) flowers.
• Root Systems


  tap root and fibrous root
• Mitosis


  part of eukaryotic cell division during which the cell nucleus divides
• Cellulous


  tough, flexible material that makes up the cell wall
• Lignin


  substance in vascular plants that makes cell walls rigid
• Dermal tissue (Epidermis)


  forms the outer layer of a root, shoot, or leaf that covers and protects the plant
• Ground Tissue


  tissue between the dermal tissue and vascular tissue of a non-woody plant that functions in photosynthesis, storage, and support
• Vascular tissue


  Plant tissue consisting of cells joined into tubes that transport water and nutrients throughout the plant body.
• Xylem


  Transports water
• Phloem


  The vascular tissue through which food moves in some plants
• Xylem Tissue


  Moves water and dissolved minerals from the roots up the stem to the leaves where these substances are used in photosynthesis.
• Phloem Tissue


  Transports glucose and other dissolved sugars from the leaves to other parts of the plant.
• Stomata


  Small openings on the underside of a leaf through which oxygen and carbon dioxide can move
• Guard Cells


  The two cells that flank the stomatal pore and regulate the opening and closing of the pore.
• Chloroplasts


  Capture energy from sunlight and use it to produce food for the cell
• Photosynthesis occurs in


  Chloroplasts
• Cellular respiration occurs in

  mitochondria
• Photorespiration


  process which involves loss of fixed carbon as CO2 in plants in the presence of light
• The stomata opens when


  Light hits the top of the leaf and simulating K ions to enter the guard cell and become turgid causing the guard cells to open
• The stomata closes when

  Sunlight is no longer pumped by active transport and they lose turgor pressure
• Transpiration


  Evaporation of water from the leaves of a plant
• Turgor Pressure


  The pressure that water molecules exert against the cell wall
• Palisade tissue cells


  column-shaped mesophyll cells in a plant leaf; responsible for photosynthesis
• Spongy tissue cells


  photosynthetic plant cells that are loosely packed to enable gas exchange, located below the palisade tissue cells in a leaf
• Lenticels


  Small raised areas in the bark of stems and roots that enable gas exchange between living cells and the outside air.
• Cohesion


  Attraction between molecules of the same substance
• Adhesion


  An attraction between molecules of different substances
• Root Pressure


  The upward push of xylem sap in the vascular tissue of roots.
• Transpiration Pull


  when water evaporates from the leaves of a plant, water is pulled up to replace what was lost.
• Phototropism


  A growth response to light
• Boysen Jensen


  phototropism occurs when the tip is separated by a permeable barrier but not an impermeable barrier
• Area of elongation


  An area of cells in the developing plant, facing away from the light source, that each elongate in a phototropic response to the light stimulus; the substance that initiates the phototropic response is auxin
• Auxin


  a plant hormone that promotes root formation and bud growth
• Gravitropsim


  plant behavior: growth as a result of gravity