How does a fish manage yo rise up and down in water?
Answers
To ascend, a fish must reduce its overall density by increasing its volume without significantly increasing its mass.
To reduce its overall density, a fish fills the swim bladder with oxygen collected from the surrounding water via the gills.
When the bladder is completely deflated, the fish has minimum volume and sinks to the ocean floor.
To stay at a particular level, a fish fills its bladder to the point at which it displaces a volume of water that weighs what the fish weighs.
Hence, it floats and sinks with the help of mainly two forces - gravity and buoyancy.
Cheers!
A swim bladder is just an expandable sac, like a human lung. To reduce its overall density, a fish fills the bladder with oxygen collected from the surrounding water via the gills. ... In this case, the forces of buoyancy and gravity cancel each other out, and the fish stays at that level.