How do sharks obtain oxygen?

Answer 1

Shark have gills, just like fish, that water flows through. Oxygen in the water is absorbed by blood rich capillaries in the gills, which then circulates the oxygen to the rest of the sharks body.

Answer 2

Sharks that live near the surface have eyes and are visual hunters. Those that live in the depths are blind. However, sharks do feed on other fish, who may feed on other fish who may eat plants, algae, and plankton, which get energy from the sun. So ultimately, yes, a shark still requires the sun for life.

Plus, sharks are cold-blooded, so they would want to live in waters warmed by the sun's rays.

Answer 3

Sharks get sun from the sun. Some that stay in the deep ocean don't need sun, and others get it by merely swimming near the surface. Basking sharks have a habit of basking in the sun, which is how they got their name.

Answer 4

Generally speaking all life in the oceans is one big food chain - which at the very bottom consists of plankton - the most abundant, and lowest form of which depend on sunlight for photo-synthesis. Without these plankton, the food chain would suffer a chain-reaction of starvation which would eventually stretch all the way up to sharks.

Other than that, the shark is not particularly dependent on the sun for light, as it tends use non-visual senses for hunting - it's sight only being good in very clear water.

It has adapted to sunlight by the colouring of is underneath being much lighter that the top side, so that prey looking up at it from below do not easily see it against the brightness where the water meets the air.