Answer to Question 1
Fluid balance is highly regulated and dependent on several essential mineralssodium and chloride ions in extracellular fluid, and potassium and phosphate ions in intracellular fluid. To maintain the right balance of ions, cells make frequent adjustments by moving electrolytes into or out of cells. Plasma proteins (albumin) help maintain healthy fluid distribution between intravascular and interstitial compartments.
Answer to Question 2
Hypokalemia or low blood potassium is not common, but can occur with prolonged diarrhea and/or vomiting (illness or eating disorder) or use of potassium-depleting diuretics. Signs and symptoms include muscle weakness, constipation, irritability, confusion, and (some studies suggest) insulin resistance. Hypokalemia can be very serious and cause irregular heart function, muscular paralysis, decreased blood pressure, and difficulty breathing.
The dorsal (red) and ventral (blue) body cavities.
Thorax Anterior view of human body
Major Body Cavities
Multiple synapses on the body of a single neuron
Fluid Compartments and Fluid Homeostasis
Pseudocoelomate body plan of a roundworm