Practice test

mutualistic relationship

both organisms derive a benefit

commensalistic relationship

one organism benefits and the other is not substantially harmed or helped

parasitic relationship

one organism benefits at the expense of the other’s health

Predation

one animal consumes another to extend its survival

Detritivores

obtain nutrients by consuming decomposing organic matter, or detritus

Scavengers

obtain nutrients from carrion or animal waste

Parasites

rely upon a living host for their nutrients

What percentage of energy is conserved at each trophic level from the level below it?

10%

Which biogeochemical cycle depends on bacteria to make the nutrient usable by plants?

nitrogen cycle 

Which of the following terrestrial biomes is mostly made up of coniferous evergreen trees that can tolerate cold winters with short growing seasons, and is located in northern Europe, Russia, and North America?

Boreal forest