Organisms living in the oceans are provided with a relatively constant environmental temperature. In order for plants and animals to make the move to land, a high cellular was critical to help maintain a relatively constant internal temperature.
A) pH
B) ion gradient
C) salt concentration
D) water concentration

What is a difference between systemic and pulmonary circulation? a. systemic circulation carries oxygenated blood to the lungs and pulmonary circulation carries deoxygenated blood to the body. b. systemic circulation carries deoxygenated blood to the lungs and pulmonary circulation carries oxygenated blood to the body. c. systemic circulation carries deoxygenated blood to the body and pulmonary circulation carries oxygenated blood to the lungs. d. systemic circulation carries oxygenated blood to the body and pulmonary circulation carries deoxygenated blood to the lungs.