-Water evaporates and condenses into clouds, then the clouds are blown over the ocean, and it rains.
-Water from a mountain flows down and into a river. The river empties into an ocean.
Chloroplasts are organelles specialized for photosynthesis. Animals do not photosynthesize; therefore, they do not need chloroplasts.
Alternative ways of representing nucleic acid chains, in this case a single strand of DNA containing only three bases: cytosine (C), adenine (A), and guanine (G). ... This structural difference is critical to the different functions of the two types of nucleic acids.
