There are a number of plants that live under the sea's surface, as well as numerous protists, fungi and bacteria.
a few of the sea animals cannot stay under water for a long time.
Practically all except for whales and dolphins, and marine birds if you count those as sea animals. Only mammals and birds are endothermic.
many aquatic animals
they have gills that aloughs them to breath
planton
Because there are many harmful sea animals who can harm humans and there is no oxygen under the sea to breathe in.
see land animals have to breathe on land...of course,and sea creatures have Gils which are used to breathe under water but their are some land and sea animals such as frogs or aquatic turtles
All sea animals swim to find food. Like for example like seals, seals find food by swimming under the sea and catch fish. sharks find food by swimming under and sea and kill fishes or other sea animals. That's is your answer; there is many more :)
green sea
green sea
No, all animals sleep at least some (except for sea sponges, coral reef, et cetera).
Youji Ohkata has written: 'Under the sea' -- subject(s): Pictorial works, Deep-sea fauna, Marine fauna, Marine animals, Deep-sea animals