Final answer:
The question deals with biological concepts such as cold-blooded organisms, fish, and sea life. It taps into the diversity within animal classes and warm-blooded adaptations of certain fish. The primary focus is on understanding traits of marine animals and exceptions within species.
Step-by-step explanation:
The question you've asked pertains to the characteristics of several biological subjects, namely aspects of cold-blooded creatures, fish, and creatures that live in the sea. These topics are intertwined with the study of animals and their habitats, with specific reference to terminology typical of biology studies.
Fish are primarily cold-blooded, which means their internal body temperature varies with the ambient environment. Many fish species do live in the sea, making the ocean their natural habitat, though not all are strictly marine as some reside in fresh water. Aquatic mammals, such as dolphins and whales, however, are warm-blooded, which is a trait that differentiates them from fish despite both living in aquatic environments.
Some fish, like the mentioned exceptions of tuna, swordfish, and some sharks, show warm-blooded adaptations allowing them to maintain a body temperature higher than the surrounding water. These exceptions highlight the diversity within animal classes and suggest that while many traits are common, variations do occur.