Heart: Fish have a two-chambered heart. Human hearts are four-chambered. Blood is pumped by the heart into the gills. Blood returns to the heart after going through the organs and muscles.
An octopus's three hearts have slightly different roles. One heart circulates blood around the body, while the other two pump it past the gills, to pick up oxygen.
The grade levels in high school and college follow the same rules as the lower class levels. The words freshman, sophomore, junior, and senior should not be capitalized unless used in a title or referring to the names of organized entities, such as “Junior Class.”
One of the best ways to eat fish bones is by deep fat frying them. Fried fish bones are actually a popular Japanese snack that can be found at many bars. If you leave some fish meat on them before frying, they'll crisp up like potato chips and be just as crunchy.