Lungs serve the purpose of gas exchange. We inhale air, drawing in oxygen (O2) and exhale air, expelling carbon dioxide (CO2). Both of these molecules are small and nonpolar, and therefore freely pass though membrane bilayers of cells in the lungs. Based on this information, the movement of O2 from the alveoli of the lungs into the bloodstream is an example of

well, you see. the answer to your question is quite simple. the thing that is big, powerful, and over 9,000 is your mom.

the answer is cell division : )

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.