how do fish servive in the ocean while the water is salty?

Answer 1

their gills scrub the oxygen from the water.

Salt water vs fresh water is of no concern to the sea fishes.

Answer 2

That is a really good question!

Saltwater fish have kidneys that are specialized for their salty environment. As with many aquatic animals, most fishes release their nitrogenous wastes as ammonia. Some of the wastes diffuse through the gills into the surrounding water. Others are removed by the kidneys, excretory organs that filter wastes from the blood. Kidneys help fishes control the amount of ammonia in their bodies. Saltwater fish tend to lose water because of osmosis. In saltwater fish, the kidneys concentrate wastes and return as much water as possible back to the body.

The reverse happens in freshwater fish, they tend to gain water continuously. The kidneys of freshwater fish are specially adapted to pump out large amounts of dilute urine. Some fish have specially adapted kidneys that change their function, allowing them to move from freshwater to saltwater.

So, basically, saltwater fish excrete nitrogen wastes as concentrated as possible, and freshwater fish pee continuously.

Answer 3

Because the fish found in the sea are salt water fish & are used to living in salt water, and cannot survive without the salt in the water now, just like a freshwater fish would not survive in the sea. I hope this helps xxx

Answer 4

Its their natural environment. Ocean salinity levels are about 1.021 to 1.027. Too much salt will speed up the breathing process which can harm the fish, and too little salt also can kill Marine fish.

The majority of species are grouped in the subclass Teleostei, with more complex vertebrae, and with a skin usually protected with scales. Most teleosts can keep neutrally buoyant when stationary in mid-water by the use of the swim-bladder, whilst sharks lack this organ and need to keep swimming or they will sink to the seabed. The swim-bladder enables fish to cope with the pressure at different depths, and is not needed in many littoral fish.

Water is a dense medium, about 830 times as dense as air, and has a greater viscosity, about 60 times that of air. This means that although marine life does not require the supporting skeletons of land dwellers, water is more difficult to swim through.

Because of this fish and other marine animals have developed shapes that minimise the resistance. This is seen clearly in the bony fish. The most efficient swimmers are streamlined forms like the Mackerel, Scomber scombrus.

Fish breathe through their gills, extracting the small amounts of dissolved oxygen in the water. They need water constantly flowing over them, inhaled through the mouth, and expelled from under the operculum, or gill cover. The fish can control the amount of water passing over the gills. This can be important in shore fishes, because water conditions and the oxygen content of rock pools are variable. Rock pool fish like the Blenny, Lipophrys pholis, can be clearly seen as the oxygen content of the water falls- leaving the water to absorb atmospheric oxygen through its skin.

Likewise they do not need fresh water to drink, as they live in a wet environment, so do not evaporate water through the skin. They get any water they need to grow, from food consumed.

100% saturation of dissolved oxygen at 3.4% salinity at 16oC = 7.9 mg/l (ppm). Higher amounts of oxygen are found in fresh water, and lower amounts as the temperature of water increases.

Answer 5

they have certain amounts of salt within their body naturally, and as long as the levels aren't too high within the content of the water the fish can survive. and i doubt that fish filter it through their gills.

Answer 6

Don't their gills filter out the bad stuff ?

Answer 7

they use their gills to filter out the salt