AP BIOLOGY

Detailed explanation-1: -Human activities have played a major role in altering the balance of the global sulfur cycle. The burning of large quantities of fossil fuels, especially from coal, releases larger amounts of hydrogen sulfide gas into the atmosphere. As rain falls through this gas, it creates the phenomenon known as acid rain.

Detailed explanation-2: -Most of the sulfur dioxide released into the environment comes from electric utilities, especially those that burn coal. Some other sources of sulfur dioxide include petroleum refineries, cement manufacturing, paper pulp manufacturing, and metal smelting and processing facilities.

Detailed explanation-3: -Health effects Sulfur dioxide affects the respiratory system, particularly lung function, and can irritate the eyes. Sulfur dioxide irritates the respiratory tract and increases the risk of tract infections. It causes coughing, mucus secretion and aggravates conditions such as asthma and chronic bronchitis.

Detailed explanation-4: -One major human activity influencing the sulfur cycle is the burning of sulfur-containing coal and oil in power plants, factories, and motor vehicles. These actions typically all add sulfur dioxide back into the atmosphere, which will once again be released into the biotic environment.