"Has the bladder of a camel" is an idomatic expression meaning that the person can drink a large amount of liquid and not need to urinate. To use another idiom, they can "hold it" very well.
The bladder wall is the outside of the bladder, the organ that stores urine.
Baby Camel
you mean gall bladder
To urinate, if you mean the urinary bladder. If you mean the swim bladder, it is to be able to change its depth in the water. It has a way to vent air from the gills to the swim bladder, and from the swim bladder to the digestive tract. So the fish would inflate the bladder to be able to rise and deflate the bladder to go lower.
Empty one's bladder means to urinate.
I have a spot on my liver, what does it mean?
2 Humps on a Camel
Assuming you mean the camel, dromedary.
camel riding
Her name is CAMILLE not Camel! XD. And if you mean by how did they get together, then..they just did. Deal with it.
The bladder is suboptimally distended with no gross abnormalities?
rapid bleeding from the bladder