What is the role of each organ?

Each organ is a system so it plays a role in what the body does which organ . I don’t have my gallbladder the dr said I don’t really need it .

It settles nerves, reduces the tension.

Because without physical activity, the body has extra "energy" if you will, and so when it is time for bed you are not tired, so you end up staying up all night. also there is probably an effect on your internal clock, which messes with your melatonin production which goes hand in hand with your sleep cycle