Maribel has a beautiful saltwater aquarium at her house. One day, a new and
inexperienced salesperson at the pet store sold her a goldfish from the freshwater tank. When Maribel placed the fish in her aquarium, it was not able to survive. What type of environment would the saltwater solution be (hypertonic, isotonic, or hypotonic) to the cells of the fish? How did you say so? Why do you think freshwater fish will not survive if placed in a saltwater?

Question

Maribel has a beautiful saltwater aquarium at her house. One day, a new and 
inexperienced salesperson at the pet store sold her a goldfish from the freshwater tank. When Maribel placed the fish in her aquarium, it was not able to survive. What type of environment would the saltwater solution be (hypertonic, isotonic, or hypotonic) to the cells of the fish? How did you say so? Why do you think freshwater fish will not survive if placed in a saltwater?

JustSaiyan · Answer

The saltwater solution would be hypertonic. What's happening is the water being sucked in and shrinking the cell because water is flowing out of the cell to dilute the salt in the tank. This causes the fish to die from dehydration. A freshwater fish would not survive in saltwater quite simply because it was not evolved to survive in that environment.