EVERYDAY SCIENCE

Detailed explanation-1: -During photosynthesis, plants take in carbon dioxide (CO2) and water (H2O) from the air and soil. Within the plant cell, the water is oxidized, meaning it loses electrons, while the carbon dioxide is reduced, meaning it gains electrons. This transforms the water into oxygen and the carbon dioxide into glucose.

Detailed explanation-2: -Natural sources of carbon dioxide include most animals, which exhale carbon dioxide as a waste product. Human activities that lead to carbon dioxide emissions come primarily from energy production, including burning coal, oil, or natural gas.

Detailed explanation-3: -The carbon atoms used to build carbohydrate molecules comes from carbon dioxide, the gas that animals exhale with each breath. The Calvin cycle is the term used for the reactions of photosynthesis that use the energy stored by the light-dependent reactions to form glucose and other carbohydrate molecules.

Detailed explanation-4: -Most carbon is stored in reservoirs, or sinks, such as rocks and sediments, while the rest is stored in the atmosphere, oceans, and living organisms. Carbon is released back into to the atmosphere through respiration by animals and plants. It is also released by burning materials such as wood, oil and gas.

Detailed explanation-5: -In animals, oxygen combines with food in the cells to produce energy for daily activity and then gives off carbon. The carbon combines with oxygen to form carbon dioxide (CO2) and is released back into the atmosphere as a waste product when animals breathe and exhale.