Robert Paine studied sea stars in the intertidal zone along the northern Pacific coast. When he removed sea stars from a study area, their prey, two mussel species, increased exponentially. This crowded out other species, and the overall biodiversity of the community was greatly reduced. What role in the community did the sea star play?
a. Pathogen
b. Keystone species
c. Producer
d. Prey species

Choose the molecule that is described by each phrase. energy used during long activities:

This question is only for applicants to scholars for medicine or scholars for dental medicine: what aspects about medicine (or dental medicine) intrigue you? describe how these aspects influence your life. (100-650 words)

This is a typical grassland food web. it is also a small picture of an important cycle on earth: the carbon cycle. describe how the carbon gets into this food web. a) bacteria and fungi, the decomposers, recycle carbon from dead organisms. b) carbon is found in the grass and is passed from one level to the next in this food web. eliminate c) all living things give off carbon dioxide as a by-product of respiration and it is released into the atmosphere. d) plants use carbon dioxide as a reactant in photosynthesis, to make usable chemical energy in the form of a sugar.