Unit 2.7-Organism Relationships

Energy is lost at each trophic level, so less is available for higher levels.

Organisms at the top reproduce more slowly.

Producers are less important than consumers.

There is more food available at the top of the pyramid.

Mutualism

Commensalism

Amensalism

Predation

Both organisms benefit

One organism benefits, the other is unaffected

One organism is harmed, the other benefits

One organism is harmed, the other is unaffected

Cattle trampling grass, harming the grass but not benefiting or harming the cattle

Tree frogs using plants for protection

Fleas living off the blood of a host animal

Owls hunting mice

Parasitism benefits one organism and harms another, while predation results in the death of one organism

Parasitism benefits both organisms, while predation harms both

Parasitism does not involve harm, while predation does

Parasitism only occurs in plants, while predation only occurs in animals

Two species competing for the same limited resource cannot both thrive.

Two species always share resources equally.

One species always becomes extinct when competing.

Species never compete for resources.