A) a common ancestor
Homologous structures are structures that are similar in related organisms. There is a basic pattern of bones which can be inherited from a common ancestor
Answer:
A
Explanation:
Before exchange, it is expected that the capillaries (that have deoxygenated blood) will have more carbon dioxide while the lungs will have more oxygen. This allows for oxygen to diffuse into the capillaries while carbon dioxide diffused into the lungs during the exchange.
Answer:
Hormones act only on cells not structures.
Explanation:
Hormones act only on cells and they do not act on other structures because there are specific cells have receptors for that particular hormone. Some hormones bind itself to the receptors on the surface of target cells whereas other hormones enter the cells and bind itself to the receptors present in the cytoplasm or nucleus of the cell.
The answer to your question is the first choice or choice A. Bacteria is a decomposer. That would be the only valid choice. If the question didn't say decomposer then all of these choices would be correct, but because it only says decomposers, bacteria would be the correct choice.