1.What are the advantages of organisms having a 4-chambered heart over less chambers?
2. The differences of Nitrogen waste elimination between most aquatic animals, mammals, and birds.
3. Do marine fish drink seawater? If so, how do they regulate the salt intake?
4. Organisms like jellyfish, sponges and flatworms do not have a circulatory system or lungs. What adaptations do these organisms have for oxygen delivery?