Predation, Parasitism, and Mutualism

These flashcards cover key concepts related to predation, parasitism, and mutualism, highlighting definitions, examples, and significant interactions in ecology.

Predation

The consumption of one living organism (the prey) by another (the predator).

True predator

An organism that kills its prey upon capture and consumes multiple prey organisms.

Grazer/browser

Herbivores that consume only part of the plant and usually do not kill the plant.

Parasite

An organism that feeds on the prey organism (host) while it is still alive, generally not lethal in the short term.

Parasitoid

An organism that lays eggs on a host, with larvae feeding on the host and usually killing it.

Microparasites

Small-sized parasites characterized by a short generation time, such as viruses and bacteria.

Macroparasites

Larger parasites with comparatively long generation times, often involving intermediate hosts, such as flatworms and ticks.

Herbivory

A form of predation where herbivores typically do not kill the individuals they feed on.

Coevolution

Occurs when prey species evolve ways to avoid being caught and predators evolve more effective means to capture them.

Mutualism

A relationship that is beneficial to both species involved.

Obligate mutualists

Species that cannot survive or reproduce without the mutualistic interaction.

Facultative mutualists

Species that can survive without the mutualistic interaction.

Secondary compounds

Chemicals produced by plants that deter herbivores or reduce their ability to digest plant tissue.

Quantitative inhibitors

Secondary compounds produced in large quantities that reduce digestibility, such as tannins.

Qualitative inhibitors

Secondary compounds present in small quantities that act as defenses against herbivory, such as alkaloids.

Mycorrhizae

A symbiotic association between fungi and plant roots that enhances nutrient uptake.

Rhizobium

Bacteria that convert N2 (g) to ammonia only through association with the roots of legumes. Invasion into the roots results in nodules where fixation occurs. In return for N, Rhizobium gets carbon and other resources.

Endomycorrhizae

A type of mycorrhizae where fungi penetrate the plant roots, facilitating nutrient exchange and enhancing plant growth by forming a finely bunched network (arbuscule)

Ectomycorrhizae

A type of mycorrhizae where fungi penetrate between plant roots, enhancing nutrient uptake while remaining external to the plant cells. Develop into a network outside the root.