1. The human immune system uses a variety of means to defend the body from pathogens. Which elements are parts of the human immune system?
A.skin, neurons, muscle cells, and pancreas
B.white blood cells and red blood cells
C.skin, lymph nodes, white blood cells, and spleen
D.mucous, urine, and kidneys
2.Which consequence occurred when sea otters were overhunted along the Pacific Coast?
A.The kelp grew rapidly and created new habitat for fish.
B.The sea urchin population was reduced to dangerous levels.
C.The sea otters on the Pacific Coast went extinct.
D.The sea urchin population expanded and consumed the kelp and damaged the habitat.
2007-06-05
08:48:35
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3 answers
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asked by
isummerlover
1
in
Biology