Submerged aquatic vegetation (SAV) plays a key role in supporting populations of fish and crabs in the shallow portions of the Chesapeake Bay and the rivers that flow into it. There are many species of underwater plants that make up SAV beds. Use what you know about photosynthesis and cellular respiration to explain why SAV beds are critical to the health of fish and crabs that live in the Chesapeake Bay. Use evidence and scientific reasoning to support your answer.