PLANT

• is toxic to humans and other ani-mals: It damages the nervous system, lungs, and liver, and exposure to large amounts can be fatal.

  TCE (trichloroethylene)
• the use of living plants to remove or degrade environmental contaminants

  phytoremediation
• The body of a vascular plant consists of two organ systems: shoots and roots.
• In a typical plant, shoots are above the ground and roots are below it.
• 3 Plant Tissues

  Dermal Tissue System, Vascular Tissue System, Ground Tissue System
• The dermal tissue system consists of tissues that cover and protect the plant's exposed surfaces.
• The vascular tissue system carry water and nutrients from one part of the plant body to another.
• The ground tissue system includes all tissues that are not part of the dermal or vascular tissue systems, and it makes up the bulk of the plant body.
• Plant tissues that consist of one cell type are called simple tissues
• Dermal and vascular tissues are complex tissues, which means they consist of two or more cell types.
• 3 Simple Tissues

  Parenchyma, Collenchyma, and Sclerenchyma
• In plants, simple tissue composed of living cells with functions that depend on location.

  parenchyma
• Collenchyma is a simple tissue that provides pliable structural support to rapidly growing plant parts such as young stems.
• In plants, simple tissue composed of cells that die when mature; their tough walls structurally support plant parts. Includes fibers, sclereids.

  sclerenchyma
• Fibers are long, tapered sclerenchyma cells; they occur in bundles that support and protect vascular tissues in stems and leaves 
• Sclereids are sclerenchyma cells that prevent the collapse of soft tissues
• The first dermal tissue to form on a plant is epidermis, which in most species consists of a single layer of epidermal cells on the plant's outer surface. 
• In older woody stems and roots, a dermal tissue called periderm replaces epidermis.
• Xylem is the vascular tissue responsible for conducting water (and substances dissolved in it) from roots to shoots.
• Phloem is the vascular tissue that conducts sugars and other organic solutes.
• The monocots and eudicots refer to one such difference, the number of embryonic (seed) leaves, or cotyledons, in their embryos.
• Monocot embryos have a single cotyledon; eudicot embryos have two
• Stems form the framework of most flowering plants, providing support and keeping leaves positioned for photosynthesis.
• regions where leaves originate

  nodes
• Xylem and phloem are organized in long, multistranded vascular bundles that run lengthwise through a stem.
• Stolons branch from the main stem of the plant and grow horizontally on the ground or just under it. They are commonly called runners because in many plants they "run" along the surface of the soil.
• rhizome serves as the primary region for storing food. They grow under the soil, and they are typically fleshier than stolons.
• A bulb consists of a short, flattened stem (a basal plate) encased in overlapping layers of thickened modified leaves called scales.
• A corm is a swollen base of a stem with a papery or netlike covering.
• Stem tubers are thick, fleshy storage structures that form on the stolons or rhizomes of some plant species.
• Many types of cacti and other succulents have cladodes, which are flattened, photosynthetic stems specialized to store water.
• Leaves are the main organs of photosynthesis in most flowering plant species. They also function in gas exchange, and they are the major site of evaporative water loss.
• A vascular bundle in a leaf.

  leaf vein
• Gas exchange occurs at stomata in the leaf's upper and lower epidermis.
• The main function of roots is the uptake of water and mineral ions from soil, but they also anchor the plant and (in some species) store nutrients.
• roots form on stems or leaves, in which case they are called adventitious roots.
• adventitious roots form aboveground at nodes on trunks or lower branches.

  prop roots
• A eudicot taproot together with its smaller lateral root branchings constitutes a taproot system
• Some eudicots store nutrients in swollen, modified lateral roots called root tubers. A sweet potato is an example of a root tuber.
• Hairlike, absorptive extensions of a root epidermal cell.

  root hairs