2. A hawk sits on a branch of a tree watching for mice. This is an example of___.

a.predation
b.mutualism
c.parasite-host
d.commensalism

3. Besides food and oxygen, what other role do marine plants do for marine
organisms?
a. habitat
b. carbon dioxide
C. light
d. all of the above
4. Which is a good characteristics of an ecosystem?
a. energy intensive
b. high biological diversity
c. low productivity
d. labor intensive
5.Coral reefs are intricately shaped rocklike structures that are formed as
a result of
a. Volcanic activity that is common in tropical marine environment
b. Minerals that are washed from land ecosystem and build up
c. The gradual accumulation and fusion of skeletons of bony fosh
d. The secretion of calcium carbonate by tiny marine animals​