Final answer:
The Florida Panthers breathe air in the atmosphere, and the melting sea ice in Alaska would most affect polar bears due to their dependence on sea ice for hunting.
Step-by-step explanation:
The air that Florida Panthers breathe is found in the atmosphere. The biosphere includes all living organisms on Earth, which rely on the atmosphere for respiratory processes. Considering the importance of sea ice for certain species, polar bears would be most affected by its melting in Alaska due to their reliance on it for hunting seals. The question of ecosystem services and the Endangered Species Act emphasize the critical role that specific populations play in maintaining biodiversity and ecological function. The irreversible nature of species extinction highlights the impact of habitat loss and climate change on global biodiversity, with ecosystems such as tropical rainforests and marine environments particularly vulnerable.