Chapter 17 Flashcards
Generalists
a species that interacts with many other species.
Specialists
a species that interacts with one other species or a few
closely related species.
Obligate mutualists
two species that provide fitness benefits to each other and require each other to persist.
Facultative mutualists
two species that provide fitness benefits to each other, but the interaction is not critical to the persistence of either species.
Mycorrhizal fungi
fungi that surround plant roots and help plants obtain water and minerals.
Endomycorrhizal fungi
fungi characterized by hyphal threads that extend far out into the soil and penetrate root cells between the cell wall and the cell membrane.
Ectomycorrhizal fungi
fungi characterized by hyphae that surround plant roots and enter between root cells but rarely enter the cells.
Arbuscular mycorrhizal fungi
a type of endomycorrhizal fungi that infects a tremendous number of plants including apple trees, peach trees, coffee trees, and grasses.
Fungal hyphae provide plants with…?
soil minerals (e.g., nitrogen) and water; plants provide the fungi with sugars from photosynthesis.
Arbuscules are…?
branching hyphal structures found within plant cells that help the fungus to provide nutrients to the plant.
Ectomycorrhizal fungi are only known to live in relationships with…?
trees and shrubs
endophytic fungi
Some plants defend themselves through mutualisms with endophytic fungi, which are fungi that live inside a plant’s tissue.
Endophytic fungi role?
produce chemicals that repel herbivores and provide drought resistance by increasing the concentration of minerals in plant tissue.
When does cheating occur?
when one species receives a benefit but does not provide one in return.
Loss of dispersers can result in…?
a reduction in plant abundance.