Pre-test: Symbiotic Relationships

Two robins eating worms on the same lawn is an example of

• mutualism

• commensalism

• competition

• parasitism

Predation is best described as

• one organism capturing and eating another

• two organisms competing for limited resources

• an interaction in which two species benefit from each other

• an interaction in which one species benefits and other is not affected

Aphids eat the sap from plants and excrete sticky waste that ants eat. The ants protect the aphids from predators. This type of interaction is called

• parasitism

• mutualism

• commensalism

• competition

An oak tree provides a sparrow a place to build a nest. The nest neither benefits nor harms the tree. What is the name of this type of relationship?

• mutualism

• commensalism

• predation

• parasitism

One difference between parasitism and predation is that parasites

• do very little harm to their hosts

• keep their hosts alive for a period of time

• attack the host only from the inside

• are not very big

Which of these is an example of parasitism?

• a lion defends its territory

• a squirrel stores food in a tree hole

• a leech feeds on a host's blood

• a polar bear kills and eats a seal