When Living beings are breathing,they get oxygen and put out carbon dioxide!
Human diploid cells have 46 chromosomes (the somatic number, 2n) and human haploid gametes (egg and sperm) have 23 chromosomes (n).
The answer is decomposers.
After the death of producers and consumers, decomposers (such as Actinobacteria, or other bacteria which are prokaryotes) eat that dead organisms and carbon, nitrogen, and other elements are released into the environment. It should be taken into consideration that eukaryotes (such as fungi) can be decomposers as well.