Multiple choice How is decomposition involved in the carbon cycle? Things take in carbon dioxide as they decompose. Things release carbon dioxide as they decompose. Decomposition is always accompanied by photosynthesis. Decomposition isn't involved in the carbon cycle. Reveal answer Fill a bubble to check yourself B Correct answer Explanation Decomposers break down organic matter, and during this metabolic process, they release carbon dioxide back into the atmosphere as a byproduct of their cellular respiration.