In the following passage there are blanks, each of which has been numbered. For each number, five words are suggested one of which fits the blank appropriately. Find out the appropriate word in each case. Greenhouse gases are only (1) of the story when it comes to global warning. Changes to one part of climate system can (2) additional changes to the way the planet absorbs or reflects energy. These secondary changes are (3) climate feedbacks…
||||
Read the passage carefully and answer the following questions A species that exerts an influence out of proportion to its abundance in an ecosystem is called a keystone species. The keystone species may influence both the species richness of communities and the flow of energy and materials through ecosystems. The sea star Pisaster ochraceus, which lives in rocky intertidal ecosystems on the pacific coast of North America, is also an example of a keystone species. Its preferred prey is the mussel Mytilus californianus. In the absence of sea stars, these mussels crowd out other competitors in a broad belt of the…
|||||||||
