Answer:
the water cycle how water evaporates from the surface of the earth, rises into the atmosphere, cools and condenses into rain or snow in clouds, and falls again to the surface as precipitation.
the series of processes by which carbon compounds are interconverted in the environment, involving the incorporation of carbon dioxide into living tissue by photosynthesis and its return to the atmosphere through respiration, the decay of dead organisms, and the burning of fossil fuels.
The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among atmosphere, terrestrial, and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes.
Answer:
A, the sun.
Explanation:
The sun powers the water cycle and many others.
RNA and DNA are both types of nucleus acids. In their names long names, they both have the words “nucleic acid” in them. Nucleic acids are composed of carbon, hydrogen, oxygen, nitrogen, and phosphorus.
The most important property of the cell membrane<span> is its selective permeability: </span>some substances<span> can </span>pass through<span> it freely, but others cannot. Small and nonpolar (hydrophobic) molecules can freely </span>pass through<span> the </span>membrane<span>, but charged ions and large molecules such as proteins and sugars are barred passage. </span>
