0
Bony fishes achieve buoyancy through an air filled sac called a swim bladder. The bladder controls the fish's buoyancy by varying the gas pressure inside the fish's body to allow it to sink or rise in the water.
Chondrichthys, or cartilaginous fishes (sharks, skates, rays) achieve buoyancy in other ways because they do not have swim bladders. They do this 3 ways:
1. Store low-density compounds in the body. They store various lipids in throughout their bodies ,which have lower densities than seawater. Squalene is one lipid that is stored in the liver of sharks.
2. Reduction of dense tissues. Chondrichthys do not have replaced bones with cartilage, which helps them reduce their weight in the water. Cartilage is 1/2 as dense as bone. They also reduce muscle mass and protein content. They also increase water content of tissues .
3. Dynamic lift. Sharks can generate lift by their swimming motion. They have a heterocercal tail with a larger dorsal lobe than the ventral lobe. This tail generates lift on the posterior end of the fish, but pushes the anterior end down. This is corrected by having large pectoral fins. This positive attack angle generates head lift. The head of a shark is also flattened dorsoventrally and counteracts the tendency for the tail to push the head downward.
The disadvantage of the Chondrichthys methods of buoyancy is that it is difficult for them to adjust their buoyancy and low density lipids are energetically expensive to make. Dynamic lift requires constant forward motion. They must keep swimming, which can also cost a lot of energy.
Cartilaginous fish stay afloat by regulating their buoyancy using their liver, which is rich in oils that are less dense than water. They also have a cartilaginous skeleton that is lighter than a bony skeleton, helping them to remain buoyant in the water. Additionally, their streamlined body shape reduces drag, allowing them to move more efficiently through the water.
Sharks for example that do not posess a swim bladder for buoyancy like many bony fishes have, must depend upon their livers. The liver contains squalene which is an organic compound that is lighter than water. The liver takes up 30% of the sharks body mass, but it is limited in use. The shark basically has to keep moving to live with it's fins. Some sharks though store air in their stomachs acting as a swim bladder to stay motionless. Also some sharks can pump water across their gills to allow them to rest at the bottom.
Fish manage to stay upright because of their equally distributed body mass and the hydrodynamics of their fins;also partially in the aero dynamics of their bulet-shaped or flat bodies. Whereas making it easier tobalance and glide through thewater and currant.^^
The fins of the fish help the fish stay upright in the water, as it is swimming.
Add your answer:
Earn +20 pts
How do fish stay afloat?
Fish are able to stay afloat due to their swim bladders, which are gas-filled organs that help regulate their buoyancy. By adjusting the amount of gas in their swim bladders, fish can control their position in the water column. The overall shape and composition of a fish's body also contribute to their ability to stay afloat and move through the water efficiently.
What are the differences between jaw less fish and cartilaginous fish?
Jawless fish, like lampreys and hagfish, lack true jaws and have circular mouths with tooth-like structures. They also have cartilaginous skeletons and lack scales. Cartilaginous fish, like sharks and rays, have jaws with teeth, cartilaginous skeletons, and covered in dermal denticles or scales.
An example of a cartilaginous fish?
An example of a cartilaginous fish is a shark. Sharks have skeletons made of cartilage instead of bone, allowing them to be more flexible and lighter for swimming. Cartilaginous fish also include skates, rays, and chimaeras.
Cartilaginous fish conduct what?
internal fertalization
Is the cartilaginous fish is the most primitive group of fish?
It is as primitive as a cave man.
Which fish can stay underwater the longest cartilaginous or bony fish?
it is the cartilaginous fish.s
How do fish stay afloat?
Fish are able to stay afloat due to their swim bladders, which are gas-filled organs that help regulate their buoyancy. By adjusting the amount of gas in their swim bladders, fish can control their position in the water column. The overall shape and composition of a fish's body also contribute to their ability to stay afloat and move through the water efficiently.
Is a tuna fish cartilaginous fish?
no. cartilaginous fishes are sharks and rays.
Do cartilaginous fish have operculum?
Jawless fish are cartilaginous, but they do not have jaws. Class Chondrichthyes, which contains most cartilaginous fish, like sharks, have powerful jaws.
Are skates cartilaginous fish or bony fish?
Similar to Stingrays, skates are cartilaginous.
What do crocodiles eat to stay afloat?
they eat small mammals,fish,crabs,frogs and birds
What are the differences between jaw less fish and cartilaginous fish?
Jawless fish, like lampreys and hagfish, lack true jaws and have circular mouths with tooth-like structures. They also have cartilaginous skeletons and lack scales. Cartilaginous fish, like sharks and rays, have jaws with teeth, cartilaginous skeletons, and covered in dermal denticles or scales.
How does the air bladder work for the fish?
no, they have a swim bladder but this is so the fish can stay afloat
Like jawless fish cartilaginous fish have sketetons made of?
Both jawless fish and cartilaginous fish have skeletons made of cartilage.
Is lizard bony or cartilaginous?
Lizards are not bony or cartilaginous fish, they are reptiles.
What does cartilaginous mean?
Cartilaginous fish have cartilaginous endoskeletons, meaning their skeletons are made from cartilage. Cartilaginous fish can also have placoid scales, or they are naked. Cartilaginous fish have gills, paired appendages, strong jaws, notochords, a dorsal nerve chord that leads to a distinct brain, and lack a swim bladder.
Why do cartilaginous fish have oil in their liver-to-do-what?
so they can float since they are full of cartilage they will sink they need to move instead of floating in one spot but the oil just helps them out by keeping them afloat while swimming.
