Final answer:
Carbon dioxide from a germinating seed is released into the atmosphere during respiration, where it becomes part of the carbon cycle. It may be stored long-term as fossilized organic matter or carbonates in rocks, or in oceans as bicarbonate ions.
Step-by-step explanation:
When a seed germinates, it undergoes respiration, a process where stored organic compounds are converted back into carbon dioxide (CO₂) gas. This CO₂ is released into the atmosphere, becoming part of earth's carbon cycle. Photosynthesis removes CO₂ from the atmosphere, while respiration, decay of organic material, and human activities such as the burning of fossil fuels, release it back.
Long-term storage of organic carbon can occur when plant matter is buried and fossilized, or in the form of calcium and magnesium carbonate in sedimentary rocks. The ocean also serves as a large carbon sink, storing carbon primarily as the bicarbonate ion.