1. Specific gravity adjustment: fish adjust the specific gravity of fish at different depths by deflating or inhaling, so that it can stay in all layers of water effortlessly.

2. Breathing function: The swim bladder of lungfish, multi-fin fish, finch eel and bowfin fish has lung function.

3. Sensory function: The swim bladder can act as a manometer or underwater microphone. Some fish swim bladders have different degrees of contact with the inner ear, so they have more sensitive hearing and stress-sensing ability.

4. Pronunciation function: The swim bladder plays the role of a buzzer for the sound produced by nearby organs, which enlarges the sound.

second, swim bladder:

most bony fishes have swim bladder. The volume of swim bladder accounts for about 5% of the body. Its shapes are oval, conical, heart-shaped, horseshoe-shaped and so on. The gas filled in the swim bladder is mainly oxygen, ammonia and carbon dioxide, with the most oxygen content. Therefore, in an anoxic environment, the swim bladder can be used as an auxiliary respiratory organ to provide oxygen for fish.

III. Nutritional components:

protein, a small biological molecule contained in swim bladder, is the raw material for human body to supplement and synthesize protein. And is easy to absorb and utilize.

It is stored in human tissues in the form of aqueous solution, thus improving the nutritional status of tissues and accelerating metabolism.

It has been proved that foods rich in collagen protein can affect the physiological functions of some specific tissues through the binding water of collagen, thus promoting growth and development, enhancing disease resistance, and playing a role in delaying aging and resisting cancer.