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The earth consists of a variety of different organisms. despite their diversity, however, some similarities on the structural and metabolic levels may be seen. these similarities can be attributed to a. similarities among organisms in their proteins and nucleic acids. b. the ability of organisms to readily adapt to sudden environmental changes. c. similarities in organisms' habitats and niches. d. the ability of all organisms to interbreed and produce new species.

Which blood cell spend most of their time in the lymphatic system?

What term describes a doctor who becomes a specialist by meeting standards beyond those of getting a license and passing a test in the specialty area?