Do Sharks Have Gills

Do Sharks Have Gills?

If you’re asking whether sharks have gills, then maybe you’re thinking of how they breathe in water. Of course, as living things, they need oxygen to stay alive. Sometimes, the question “do sharks have gills?” come to mind when you wonder if sharks are actually fish or mammals.

So, do sharks have gills? Simply put, sharks have gills. As a matter of fact, the breathing process of sharks begins and ends with their gills. Note that sharks are fish and not mammals. Hence, like every other fish, they have gills. They make use of their gills for gaseous exchange in water. Unlike terrestrial animals, sharks don’t have to breathe air to survive. They always transform their oxygen from the water with the help of their gills.

Some shark species can pump water over their gills through their mouth. They achieve this through buccal pumping which involves using their cheek muscles to draw water into their mouth. Meanwhile, others let water flow through their gills while they swim or move around the water.

Sharks do not breathe on dry land. As a result, they can only stay alive on dry land until the water in their gills dries off. This entails that sharks’ gills are specifically meant for breathing inside the water.

Do Sharks Have Nose?

Sharks have an acute sense of smell. Though, over the years their sense of smell has been exaggerated.

Sharks Nose is located under their snouts. Unlike human nostrils, sharks own is solely meant for smelling and not for breathing. Therefore, they can perceive a smell when water flows into their nostrils.

When water flows into their nostrils a dissolved chemical will contact tissues. This sends a signal to the brain and it interprets it as smell.

What Do Sharks Breathe With?

Sharks rely solely on their gills to breathe. They use their gills to extract oxygen from water and rid their bodies of carbon dioxide.

The gills are made up of branched or feathery cellular tissue richly supplied with blood vessels. This is mostly near the gill surface. It facilitates the exchange of oxygen and carbon dioxide with the surrounding water. This process is called countercurrent.

Unlike other ocean giant fishes (whales and dolphins) that breathe through their lungs, Sharks don’t have lungs. But they do need to breathe oxygen to survive just like other fish. Instead of breathing air, sharks get oxygen from the water that surrounds them using their gills.

The concentration of oxygen in the water which is just a fraction of 1 percent is much lower than in air which is 21 percent. So, sea animals like sharks developed ways to harvest as much oxygen as they can. This is through the use of their gills because they all need oxygen to be alive.

While sharks are in motion, water moves in and out from their gills. This is the process of ram ventilation. While at rest some sharks pump in water through their mouth over gills (buccal pumping) to enable gas exchange.

Most aquatic fish who do not have the capacity for buccal pumping will keep swimming to maintain gaseous exchange. As a result, they don’t rest, but keep swimming till they die.

How Many Gills Do Sharks Have?

Sharks normally have 5 pairs of gill slits found on the sides of their heads. But there is the Notorynchus cepedianus (7-gill sharks) and the Bluntnose sixgill, which uniquely have 7-gill slits and 6 gill slits respectively.

With this, you can say that the range of shark gills is from 5 to 7gills. Unlike bony fish, sharks don’t possess gill covers.

Sharks, just like every other fish, live in the water and use their gills to extract oxygen from the water. When water passes over the gills, a system of very fine blood vessels (capillaries) in the gills absorbs oxygen from the water.

Sharks do not have lungs but still trap oxygen and maximize it using its gills. So, sharks trap the right amount of oxygen using their gills.

It is good to note that shark gills comprise of the gill slits, gill rakers, and the gills filaments. Gill rakers are tiny bony or cartilaginous projections across the gill slit. Their function is to help keep food or other tiny prey from getting out through the slits or causing damages to the gills.

The gill filaments are the essential respiratory organs of gaseous exchange. They are the reddish, fleshy components of the gills. Gill filaments are primarily responsible for taking in oxygen into the bloodstream of the shark.

Each filament has thousands of tiny fine branches called lamellae. The lamellar is exposed to the water.

The gills slits are the individual openings of the gills. A Complete gill is called a holobranch.

How Many Gills Do Great White Shark Have?

The great white has 5 gill slits and a mouth extension behind the eyes. The number of gill slits is not dependent on the size and length of a shark but on the adapting nature of the shark. Hence, no matter the size of a great white shark, it will have only 5 gill slits.

Just like the Notorynchus cepedianus (7-gills sharks) and Bluntnose six gills. They uniquely have 7-gill slits and 6 gill slits due to the fact that they are normally found on the deepest part of the ocean.

Though they are relatively small compared to the great white shark, they have more gill slits. This is because the deeper the depth of the oceans the lower the level of oxygen. Therefore, it is justifiable that sharks living in such zones have more gills.

The great white shark lives in the open sea. They live close to the coast, in all warm waters, and occasionally make dives into the deep water of open oceans. So, having 5 gills is adapted for their nature.

Why Do Sharks Have Gills?

The main respiratory organ of sharks is their gills. Consequently, sharks use their gills to filter oxygen from water and rid their bodies of carbon dioxide.

Now take a look at the quick explanation of how the respiratory cycle of sharks works.

As water passes over the gills, small capillaries extract into the bloodstream. The blood which contains oxygen is then pumped throughout the shark’s body.

Likewise, Carbon dioxide waste also passes through the gills from the blood out of the shark’s body. Then, the process starts all over.

Can Sharks Breathe on Dry Lands?

No! sharks don’t breathe outside the water. Just like I stated above the gills are specifically meant to breathe in water.

Although sharks have nostrils, they don’t breathe with their nostrils. Their nostrils are basically an organ of smell. They can’t breathe with their nostrils, instead, they only breathe with their gills.

Gills are specifically meant for breathing inside the water. Meanwhile, sometimes these aquatic animals find themselves on dry land. Whatever is the reason that sharks are on dry land, they can’t breathe in air.

The sharks tend to breathe on land as long as the water on their gills doesn’t dry off. Once the water dry’s off, the shark can’t breathe anymore. This is because they convert their oxygen from the water.

The end result of this is the death of the shark.

Do Sharks Have External and Internal Gills?

Sharks use their gills to extract oxygen from the water around them, and through the gill slits, they also expel carbon dioxide from the blood. Out of the many species of sharks in the ocean, the majority have five gill slits. However, there are exceptional sharks with six or even seven gill slits.

As the gill arches provide support for the gills, they are considered to be part of the shark’s skeletal system. The arches would keep one or two rows of gill filaments in place.

The design of the gill filaments is in such a way that water flows only in one direction across them. Meanwhile, the filaments contain blood vessels in which blood flows in opposite direction as the water.

This is the countercurrent system. It is basically the most effective oxygen and carbon dioxide exchange system between the water and blood.

Generally, on each side of a bony fish, there is four gill arch which an external bony plate covers to offer protection to it. Sharks gills are more vulnerable to injuries because they do not have an external bony. The protective plate covers it, unlike the bony fish.

Most sharks have spiracles which are usually in pairs. The spiracles are more prominent in sharks living at the bottom of the sea. This is because it helps them take in the water when they hide in the sand. You’ll find spiracles in the form of a hole between the sharks’ eye and the gill slits.

Some sharks must swim to ensure the circulation of oxygen and carbon dioxide in their gills. As a matter of fact, they have to keep up with a certain swimming speed to let the water flow through their mouth and over their gills.

Other sharks have some more developed muscles in their cheek and throat that help them draw in water through the mouth even when they are still.


Sharks have gills which they use for gaseous exchange. This page also covers the functions and components of gills.

Sharks’ gills are very crucial organs for these sea creatures. They play an important role to keep these sharks alive.