DISSECTING

• Dissection of animal organs


  A method of biology teaching that offers a direct and authentic view into morphological structures and enables hands-on activity and multisensory experiences
• The dissection process is often associated with certain (negative) emotions that might hinder successful learning
• Plant dissection


  1. Choose one of your flowering plants

  2. Use your hands, scissors or tweezers and carefully take apart your plant

  3. Carefully remove the petals from the flower (you can use scissors or gently pull the petals off)

  4. Use the hand lens and/or dissecting microscope to examine the filaments
• Function of each part

  Describe the function of each part of the flower
• Scientific name of flower

  Provide the scientific name of the flower
• Flowering plants


  Plants that produce seeds enclosed in an ovary
• Anthophyta


  A group of plants that produce flowers and bear seeds inside the fruits
• Coniferophyta


  A group of plants that do not produce flowers and bear naked seeds
• Monocotyledonae and Dicotyldonae


  The two classes of the phylum Anthrophyta, also known as monocots and dicots
• Plants


  • Multicellular eukaryotes whose bodies are composed of organs, tissues, and cells with highly specialized functions
  • Tissues are groups of similar cells that work together on a specific task
  • Organs are structures made up of two or more tissues organized to carry out a particular function
  • Groups of organs with related functions make up the different organ systems
• Organ systems in seeded plants

  • Root system
  • Shoot system
• Root system


  Supports the plants and absorbs water and minerals, usually underground
• Shoot system


  Consists of stems, leaves, and the reproductive parts of the plant, generally grows above ground and absorbs light needed for photosynthesis
• Organs in seeded plants

  • Roots
  • Stems
  • Leaves
• Tissue types in seeded plants

  • Ground tissue
  • Vascular tissue
  • Dermal tissue
• Roots


  • Anchor the plant to the soil
  • Absorb water and minerals and transport them to the shoot system
  • Store the products of photosynthesis
• Root systems

  • Tap root systems
  • Fibrous root systems
• Tap root systems


  Have a main root that grows down vertically and many smaller lateral roots arising from the tap root, penetrate deep into the soil and are advantageous for plants growing in dry soils, common in dicots
• Fibrous root systems


  Located closer to the surface and have a dense network of roots, can help prevent soil erosion, common in monocots
• Stems


  • Provide structural support to the plant, holding leaves, flowers and buds
  • Connect the roots to the leaves, transporting absorbed water and minerals from the roots to the rest of the plant, and transporting sugars from the leaves (the site of photosynthesis) to desired locations throughout the plant
• Leaves


  Main sites for photosynthesis, the process used by plants to synthesize food, typically green due to the abundance of green chlorophyll in the leaf cells, but may have different colors caused by other plant pigments
• Typical eudicot leaf structure

  • Petiole, which attaches the leaf to the stem
  • Veins, which are bundles of vascular tissue that run through the leaf and carry water and nutrients, and also provide structural support to the leaf
• Plant tissues


  • Meristematic tissue
  • Permanent (or non-meristematic) tissue
• Meristematic tissue


  Functionally equivalent to stem cells in animals: undifferentiated cells that continue to divide and generate new cells and new tissues
• Permanent tissue


  Plant cells that are no longer actively dividing
• Tissue types produced by meristems

  • Dermal tissue
  • Vascular tissue
  • Ground tissue
• Dermal tissue


  Covers and protects the plant, and controls gas exchange and water absorption
• Vascular tissue


  Transports water, minerals, and sugars to different parts of the plant, made of xylem which transports water and provides structural support, and phloem which transports sugars from sites of photosynthesis to other parts of the plant
• Ground tissue


  Carries out different functions based on the cell type and location in the plant, including photosynthesis, structural support for the stem and the vascular tissue, and storage for water and sugars
• Dermal tissue cell types

  • Epidermal cells
  • Guard cells
  • Root hairs
  • Trichomes
• Xylem tissue


  Transports water and nutrients from the roots to different parts of the plant, composed of vessel elements and tracheids which are tubular, elongated cells that conduct water
• Phloem tissue


  Transports organic compounds from the site of photosynthesis to other parts of the plant, consists of sieve cells which conduct sugars and other organic compounds, and companion cells which provide metabolic support and regulation
• Ground tissue cell types

  • Parenchyma, which carry out photosynthesis in the leaves and performs sugar storage in the roots
  • Collenchyma, which supports the stems and leaves in areas of active growth
  • Schlerenchyma, which supports the stem and leaves in areas where growth has ceased