Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

A skeleton that consists of hard, mineralized structures located within the soft tissue of organisms is called endoskeleton.
A skeleton that consists of hard, mineralized structures located within the soft tissue of organisms is called what?

In machines that increase force, such as ramps and doorknobs and nutcrackers, output is greater is the relation between output and input force.
In machines that increase force, such as ramps and doorknobs and nutcrackers, what is the relation between output and input force?

Sickle-cell disease significantly impairs the function of circulatory system.

Sickle-cell disease significantly impairs the function of what?