The principle characteristic distinguishing marine and freshwater ecosystems is

Consider an organism that is eukaryotic, found in both unicellular and multicellular forms, may resemble a plant but is not photosynthetic, has chitin in its cell walls, and absorbs organic nutrients from decomposing material in the environment. this organism would be classified as which of the following types of organisms? a. fungib. protozoac. bacteriad. archaea

Identify two examples of chemical reactions that you have encountered during the last week. identify an exothermic and endothermic reaction. explain.

Which of the following must be true for a fossil organism to be useful as an index fossil? a. the fossil organism must be widespread geographically. b. the fossil organism must be abundant. c. the fossil organism must be limited to a short span of geologic time. d. all of the above.