plants isu

• VOCAB


  • Vascular tissue
  • Vascular
  • Non-Vascular
  • Gymnosperms
  • Angiosperms
  • Monocots
  • Dicots
  • Conifers
  • herbacious
• Probable that vascular and non-vascular plants have a common ancestor with the protist green algae
• Both vascular and non-vascular plants use starch as their primary food source, have cellulose in their cell walls, and use a and b chlorophylls during photosynthesis
• Members of the plant kingdom live in terrestrial environments (wetlands, deserts, tundra, tropical rain forests)
• Plants have adapted to protect their reproductive cells and have more sophisticated ways of transporting material to and from their environment within the plant
• Non-Vascular Plants


  • Require a moist environment because they cannot reproduce unless there is a film of moisture available to carry gametes between plants, and because they lack vascular tissue, which means they have no system of tubes to carry water and dissolved substances through the plant
• Non-Vascular Plant Structures


  • Cannot have true roots, stems, or leaves even if they appear so because they do not carry vascular tissue
  • The rootlike structures anchor the plant, but do not absorb water for it
  • The stemlike structures hold up the leaf like structures but cannot transport food or water
  • The leaf like structures carry out photosynthesis and make food, but the dissolved food must diffuse to other parts of the plant
• Non-Vascular Plants


  • Restricted in size because they cannot grow very tall, due to the lack of specialized vascular tissue to support them or to bring water upward
  • Only play a minor role of providing food or other materials for people
• Non-Vascular Plants


  • Sphagnum moss
  • Princess pine
• All trees and many of our food plants are vascular, as are the food plants used to nourish domestic animals such as poultry and cattle
• Many early forms of vascular plants are now extinct, and only a few groups of plants still exist today
• Existing groups of vascular plants

  • Whisk ferns
  • Club mosses
  • Horsetails
  • Ferns
• Gymnosperms


  Trees that have specialized leaves and cones
• Angiosperms


  Trees that have leaves and acorns
• Both gymnosperms and angiosperms grow from seed, which is a complex multicellular structure that contains an embryo and a food supply
• Gymnosperms


  • Have seeds without a seed coat and are attached to the scales of cones
  • Many are adapted to thrive in environments with long cold winters and low amounts of nutrients in the soil
  • Dominate in large parts of Canada, northern Europe, and northern Asia
  • Provide fibre for making paper and wood for building materials
• Angiosperms


  • The total number of angiosperm species is far greater than the total number of gymnosperm species
  • More diverse in structure than gymnosperms
  • Widely distributed around the world
  • Important as a source of food for many organisms, including humans
  • Also known as flowering plants
  • Flowers are the angiosperm's reproductive organs, which mature into a seed-containing fruit
  • The extra protection of the surrounding fruit gives angiosperm seeds a strong adaptive advantage over gymnosperm seeds, which lack an enclosing fruit
  • Fruits are adapted to facilitate seed dispersal
• Types of angiosperms


  • Trees
  • Grasses
  • Vegetables
  • Wildflowers
  • Herbs
• All angiosperm seeds have either one or two (never more) embryonic seed leaves, or cotyledons, inside the seed
• Monocots


  Angiosperms that have one cotyledon
• Dicots


  Angiosperms that have two cotyledons
• Monocots are non-woody or herbaceous (their stems are soft and fleshy)
• The most important monocots are the grasses
• Cows and rabbits can eat grasses


  They have bacteria in their digestive systems that produce enzymes able to cut the "crossties" in cellulose molecules, and thereby release glucose units
• Humans cannot digest grass blades (leaves) because we do not have the enzymes needed to break down the cellulose
• Humans do eat the seeds of grasses
• Vascular tissue


  • Specialized tissue for transporting material from one location to another within the plant
  • Consists of an internal system of tubes that transport water and dissolved food throughout the plant
• Vascular bundles in dicot stems

  • Form a discontinuous ring
• Vascular bundles in monocot stems

  • Scattered throughout the stem in no discernible pattern
• The vascular bundles in a stem are continuous, tube-like strands connecting the vascular tissue of the root to the vascular tissue in the leaves
• Xylem


  Specialized tissue in vascular bundles that carries out the transportation of water
• Phloem


  Specialized tissue in vascular bundles that carries out the transportation of food (translocation)
• Translocation is the transportation of food from one region in a plant part to another region
• Translocation in phloem


  • Moves food from regions of low concentration to regions of high concentration
  • Cannot be explained by simple diffusion
  • Carried out by the living cells in phloem using their own cellular respiration
• Starch is insoluble in water, so the dissolved food being transported by the phloem is sucrose
• Food stored in a tree's roots is starch, but this food cannot be transported through the stem in the form of starch. It must be broken down chemically into sucrose so it can dissolve in water
• The sap that floods upward through the phloem of maple trees in spring contains large amounts of sucrose
• Once the maple sap is delivered to the immature buds, the sucrose is further broken down into glucose to provide energy for the buds to divide and grow
• Once the leaves are producing more glucose than they require, the excess glucose is converted into starch grains in the chloroplasts
• The starch in the roots is then broken down to form sucrose, which travels from the leaves to the root by way of the phloem tissue in the stem