Answer and Explanation: The excretory system helps the respiratory system by getting rid of carbon dioxide. The respiratory system helps the excretory system by getting rid of CO2 from the body. They both need each other and if one or the other did not exist, we might've not been able to survive. Tis demonstrates how vital they are for the human body.
Answer:
Environmental factors such as diet, temperature, oxygen levels, humidity, light cycles, and the presence of mutagens can all impact which of an animal's genes are expressed, which ultimately affects the animal's phenotype.
Explanation: