Ecology Chapter 13 and 14 ECU

  1. 1st
  2. NPP =
    production of organic compounds from CO2, principally through the process of photosynthesis
  3. Commensalism—
    individuals of one species benefit, while individuals of the other species do not benefit and are not harmed (+/0).
  4. Mutualism—
    mutually beneficial interaction between individuals of two species (+/+).
  5. mycorrhizae,
    symbiotic associations between plant roots and various types of fungi.
  6. Ectomycorrhizae—
    the fungus grows between root cells and forms a mantle around the exterior of the root.
  7. Arbuscular mycorrhizae—
    the fungus grows into the soil, extending some distance away from the root; and also penetrates into some of the plant root cells.
  8. Mammalian herbivores such as cattle and sheep depend on
    bacteria and protists that live in their guts and help metabolize cellulose.
  9. Some positive interactions are highly species-specific, and obligate, meaning?
    (not optional for either species).
  10. Habitat mutualisms—
    one partner provides the other with shelter, a place to live, or favorable habitat.
  11. Trophic mutualisms—
    a mutualist receives energy or nutrients from its partner.
  12. Service mutualisms—
    interactions in which one partner performs an ecological service for the other.
  13. Trophic mutualisms
    Example: Leaf-cutter ants and fungus.In mycorrhizae, the fungus gets energy in the form of carbohydrates and the plant gets help in taking up limiting nutrients, such as phosphorus.
  14. Service mutualisms
    Ecological services include pollination, dispersal, and defense against herbivores, predators, or parasites.
  15. Sometimes the cost is clear in the form of
    —a “reward” for a service. During flowering, milkweeds use up to 37% of the energy gain from photosynthesis to produce nectar that attracts insect pollinators.
  16. Concept 14.1: Positive interactions occur when neither species is harmed and the benefits of the interaction are
    greater than the costs for at least one species.
  17. Concept 14.2: Each partner in a mutualism acts to serve
    its own ecological and evolutionary interests.
  18. Concept 14.3: Positive interactions affect the distributions and abundances of organisms
    as well as the composition of ecological communities.
  19. But when predators are few, the
    tree-hoppers may get no benefit from the ants. The interaction may shift from
    +/+ to +/0.
Card Set
Ecology Chapter 13 and 14 ECU
Ecology Chapter 13 ECU 14