Learning Objectives

4.3.1 List the three factors that influence the movement of water from a high-energy state to a low-energy state (i.e., with reference to water potential gradients) in biological systems.

4.3.2 Explain how organisms can control water gains and losses by adjusting resistance to water movement, and describe how high resistance may involve trade-offs with other functions.

4.3.3 Describe how salt and water balances can become challenges for organisms exposed to hyperosmotic and hypoosmotic environments.