What does the earth food chain start with

Which of the following protists gets nutrients mainly by absorbing molecules from other organisms through their cell walls and cell membranes? a. amoebas b. water molds c. ciliates d. slime molds

Select the correct answer from each drop-down menu. in an experiment, dr. travis examined the effects of calcium intake on osteoporosis, a condition that causes an increased risk of bone fractures. the amount of calcium is variable. the risk of bone fractures .

For a comparative or experimental investigation, scientists often make a testable about a scientific question, and then they test it in the investigation. a.control b.hypothesis c.procedure d.system