Most aquatic organisms are adapted to a narrow range of salinity. why must aquatic organisms living in coastal areas be adapted to survive in both low and high salinity?

during high tide, freshwater mixes easily with ocean water, lowering salinity.
during low tide, the ocean water becomes concentrated, increasing salinity.
ocean currents bring in deep-ocean water with high salinity concentrations.
temperature fluctuations can cause changes in the salinity levels of the water.

In terms of alternation of generations, the internal parts of the pollen grains of seed-producing plants are most similar to a ) moss sporophyteb) moss gametophyte bearing both male and female gametangiac) fern sporophyted) fern gametophyte bearing only antheridia

How do adaptation affect a species?

The human genome project is devoted to mapping the general dna sequence of our species. this could lead to the development of new medicines, as well as the possibility of using gene therapy to treat certain diseases. however, there are some ethical issues surrounding the mapping of individual genomes. one concern is a) that your genes may change over time, making the project useless. b) that insurance companies could discriminate based on genetic make-up. c) that since this has never been done before, we should probably not do it now. d) that sequencing our individual genomes is so expensive, it is a counter-productive strategy.