Compare and contrast the gas exchange systems of fish and mammals in relation to their environments.  (hint: fish have a system that works well in water; mammals have a system that works well in air. explain why each system works in its particular environment. your answer should include a discussion of countercurrent exchange.)

Many state and local authorities are making laws regarding recreation on lakes, rivers, and oceans to reduce water pollution. why would lawmakers need to consult with scientists before making these laws? a) to make scientists feel important b) so that the laws reduce pollution by a sufficient amount c) so that parks and lakefront facilities will still make large profits d) so that the public will believe that the laws are important to follow

What is it called when plants lose water though their leaves

Apaleontologist finds a plant fossil that shows that the plant had seeds. what can the paleontologist conclude?