The brain and central nervous system
The process that exerts the greatest control over the water balance of an individual is renal function, specifically through the regulation of urine production and reabsorption of water in the kidneys. The kidneys play a vital role in maintaining water balance by adjusting the volume and concentration of urine depending on the body's hydration status. Hormones like antidiuretic hormone (ADH) and aldosterone also play key roles in regulating water balance by influencing how much water is retained or excreted by the body.
It would be hard. You need to be able to keep you heart beating at all times to keep your blood flowing to all parts of your body. You would be in control or your body more than the body would control you. You would have to heal cuts and keep everything in your body alive. (That's a lot of stress on you!)
brain
Mammals lose solutes through bodily fluids like urine, sweat, and feces. These fluids contain dissolved ions and molecules that are excreted from the body to help maintain proper balance of solutes in the body.
The human brain has 19 if not more; the frontal lobe, temporal lobe, occipital lobe, parital lobe, white matter, thalamus, hypothalamus, pituitary gland, olfactuary gland, hippocampus, cerebellum, medulla oblongota, midbrain, rectengular nerves, right hemisphere, left hemisphere, pineal gland, and corpus callosum. satysfied?
aldosterone
The kidney exerts primary control over sodium levels in the body by regulating the reabsorption and excretion of sodium ions in the urine. Hormones such as aldosterone also play a key role in controlling sodium levels by influencing the reabsorption of sodium in the kidney.
fascism
Basically you have control over the voluntary muscular system (and the bones it's connected to).
RNA
RNA
The process that normally exerts the greatest control over the water balance of an individual is urinary excretion. The body systems dispose of a type of waste directly to the environment is digestive system, respiratory system, integumentary system, and urinary system.
What_is_the_sensitive_area_of_the_small_intestine_which_exerts_control_over_the_entire_digestive_tractAccording to this the "Duodenu".
The reticular formation in the brain stem
One country's control over another is typically referred to as imperialism or colonialism, where a more powerful country exerts influence, control, or authority over a less powerful country or region.
probably the duodenum
Duodenum: the upper chamber of the Small Intestine.