The ice cubes were floating in water because they are less dense than liquid water. When water is frozen, a structure that is crystalline is formed that is held by hydrogen bonding. Due to the orientation of these bonds, the moleules would push far away from each other causing it to have a bigger volume and a lower density.
Answer: This is an example of downregulation and upregulation.
Explanation:
Downregulation is a process in which cells decrease the production of one of their components, responding to an external stimulus. Upregulation, on the other hand, is when cells increase the production of one of their components in response to an external stimulus.
In this case, the decrease in insulin receptors would make the cell less sensitive to the hormone.
If there's a lot of insulin around those cells, the cell would have to decrease its sensitivity, otherwise, it would metabolise more glucose than the body needs. The contrary would happen if there was too little insulin around those cells, they would have to become more sensitive to it by increasing the number of receptors.