Aquatic Plants The Flowering Plants That have returned to Aquatic Environments
Why go back to the water? • Support from water • Less need for strong, thickened stems • Must be flexible to move with currents or waves • Therefore they are all herbaceous (no shrubs/trees) • Protection in the water • Water as a medium for sexual reproduction • Emergent option (feet in the water, heads in the air) • Earth has a lot of water (marine, fresh, and brackish) • 79 families and 380 genera have made the switch!
Adaptations • Leaves • Often long and narrow, with a central cluster or non-thickening conducting tubes • Stems • Spongy stem tissue through which gases can diffuse • To help ‘pump’ oxygen to the submerged roots • Roots • May have tuber-producing rhizomes • Flowers • Pollination and seed dispersal via insects and wind/water • Pollen grains are thread-like, why do you think this is?
Asexual Reproduction • Very important in aquatic plants! • Resulting in extensive ‘clones’ of genetically identical plants in the surrounding area
Who uses them? • Aquatic Food Webs • Fed upon by aquatic organisms (or indirectly) • Provide habitat or hunting areas • By blocking sunlight, the keep algae blooms down • Human Uses • Materials for food • Clothes, mats and baskets • Removal of invasive species, which choke waterways
BC Native • Yellow Pond Lily • Nupharpolysepalum
BC Native • Common Eel-Grass (Zostera marina) • The flowers are released to float upwards, cool eh?
Our Bio11 Floaters! • Water Hyacinth • Water Lettuce • Take a sample to draw in actual size • Then view plant tissues with microscopes • Complete a sketch of the field of view for close up of leaves, stems, and roots • This will be handed in by tomrorow • Come after school for more microscope time