Carbon dioxide because people in other animals exhale carbon dioxide as a waste product. People and other animals need oxygen for plants produce oxygen during an important process called photosynthesis which turns the sun energy into nutrients so carbon dioxide would be the answer.
Essentially wetlands<span> are the transition </span>between<span> dry land and water (streams, </span>rivers,lakes<span>, and coastlines), </span>wetlands<span> take many forms including the familiar marshes, swamps and bogs. Yet, not all </span>wetlands<span> are "wet" year round. These "drier end"</span>wetlands<span> also perform significant </span>wetland<span> functions.
Hope i helped :)</span>
The human body uses amino acids to produce protein
essential amino acids are obtain by food