Complex molecules are made up of carbon<span> bonded with other elements, especially oxygen, hydrogen and nitrogen, and </span>carbon<span> can bond with all of these because of its four valence electrons. </span>
Answer: The role an organism plays in its community is its niche. I Know this is right cause I took this test last year in 11 grade.
during active, transport, substance move against the concentration gradient, from an area of low concentration to an area of high concentration. This process is active because it requires the use of energy. <em>It</em> <em>is</em><em> </em><em>t</em><em>he</em><em> </em><em>opp</em><em>osite</em><em> </em><em>of</em><em> </em><em>passive</em><em> </em><em>trans</em><em>port</em><em>.</em>
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