How has fish adapted to its environment to minimized water resistance?

Fish breathe by drawing water in their mouths and forcing it out of the body via a number of gill slits. The gill slits are rich in blood vessels, enabling the direct absorption of oxygen. While all fish have gills, some fish are also able to extract oxygen from the air via gulping.

Most fish have swim bladders that are permanently sealed, but other fish have swim bladders that can hold varying amounts of air. Salmon have open swim bladders, and they must gulp air at the surface to keep them full. Some fish, such as sharks, lack swim bladders entirely. This causes them to sink if they do not maintain forward motion.

Fish have fins that are adapted to their lifestyle. Some have evolved into long, barbed structures, suitable for defense. Other fish have fins suited for achieving great speed or for walking along the bottom of the ocean.

Fish breathe by drawing water in their mouths and forcing it out of the body via a number of gill slits. The gill slits are rich in blood vessels, enabling the direct absorption of oxygen. While all fish have gills, some fish are also able to extract oxygen from the air via gulping.

Most fish have swim bladders that are permanently sealed, but other fish have swim bladders that can hold varying amounts of air. Salmon have open swim bladders, and they must gulp air at the surface to keep them full. Some fish, such as sharks, lack swim bladders entirely. This causes them to sink if they do not maintain forward motion.

Fish have fins that are adapted to their lifestyle. Some have evolved into long, barbed structures, suitable for defense. Other fish have fins suited for achieving great speed or for walking along the bottom of the ocean.

prism b but im not for sure

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."