Which is an example of mechanical weathering? A.) carbonic acid in water dissolving limestone

B.) salt crystallization weathering

C.) water combining with rock crystals to form hydrates

D.) colonies of bacteria releasing chemical enzymes and acids that break down minerals

In which of the following ways is the function of the surface of a microsphere similar to the function of an actual cell membrane? a.both make it possible for the conditions in the interior to be different from the conditions outside. b.both provide a barrier that keeps water from flowing across it so the interior remains dry. c.both separate the rna that forms in the interior from any rna that might form in the environment. d.both can actively move molecules into the interior or out into the surrounding environment.

When does the circulatory system work with the respiratory system? a. during blood cell formation b. during cellular respiration c. during intestinal digestion d. during a viral infection

Which macromolecule catalyzes chemical reactions this be considered enzyme chemical reactions thus he considering enzymes