Answer:
When sulfurous, sulfuric, and nitric acids in polluted air and rain react with the calcite in marble and limestone, the calcite dissolves. In exposed areas of buildings and statues, we see roughened surfaces, removal of material, and loss of carved details. Stone surface material may be lost all over or only in spots that are more reactive.
Explanation:
You might expect that sheltered areas of stone buildings and monuments would not be affected by acid precipitation. However, sheltered areas on limestone and marble buildings and monuments show blackened crusts that have peeled off in some places, revealing crumbling stone beneath. This black crust is primarily composed of gypsum, a mineral that forms from the reaction between calcite, water, and sulfuric acid. Gypsum is soluble in water; although it can form anywhere on carbonate stone surfaces that are exposed to sulfur dioxide gas (SO2), it is usually washed away. It remains only on protected surfaces that are not directly washed by the rain.
Digestion, Absorption, Circulation, Diffusion, Synthesis.
Digestion begins as soon as you put food in your mouth and begin chewing it, so it is the first step. Absorption happens when food is converted into substances that can be absorbed by your GI tract. Circulation is where those nutrients are circulated in your lymphatic and circulatory system (blood). Diffusion moves oxygen through your blood stream where it gets diffused. S<span>ynthesis converts nutrients that have been diffused and absorbed in your blood. </span>
Natural selection can cause speciation, which increases the biodiversity of an ecosystem. Several bacterial colonies are placed on a petri dish that contains agar with antibiotics. After 24 hours, ninety percent of the original bacteria die, but the remaining ten percent survive and later reproduce.
