[04] Fluid and Electrolyte Balance Flashcards
What role does the urinary system play in maintaining fluid and electrolyte balance?
It regulates the volume and composition of body fluids by adjusting the amounts of water and electrolytes excreted in urine
How do kidneys maintain fluid balance in the body?
By adjusting urine production based on the body’s hydration levels
How do kidneys maintain electrolyte balance in the body?
By reabsorbing necessary ions and excreting excess ions in urine
What role does ADH play in fluid balance?
ADH promotes water reabsorption in the kidneys, reducing water loss in urine and helping to maintain fluid balance
What role does aldosterone play in electrolyte balance?
Aldosterone promotes sodium reabsorption and potassium excretion in the kidneys, helping to maintain electrolyte balance
What electrolytes do the kidneys help regulate?
- Sodium
- Potassium
- Calcium
- Chloride
- Magnesium
- Phosphate
- Bicarbonate
What happens if there is too much water in the body (overhydration)?
The kidneys excrete more water in urine to restore fluid balance
What happens if there is too little water in the body (dehydration)?
The kidneys conserve water by producing less urine to restore fluid balance
What happens if there is too much sodium in the body (hypernatremia)?
The kidneys excrete more sodium in urine to restore electrolyte balance
What happens if there is too little sodium in the body (hyponatremia)?
The kidneys conserve sodium by reabsorbing more sodium from urine to restore electrolyte balance
How does ADH secretion change in response to overhydration?
ADH secretion decreases to increase water excretion
How does ADH secretion change in response to dehydration?
ADH secretion increases to decrease water excretion
How does aldosterone secretion change in response to high blood sodium levels?
Aldosterone secretion decreases to increase sodium excretion
How does aldosterone secretion change in response to low blood sodium levels?
Aldosterone secretion increases to decrease sodium excretion
How does the urinary system respond to high blood potassium levels?
It increases potassium excretion in urine
How does the urinary system respond to low blood potassium levels?
It decreases potassium excretion in urine
How does the urinary system respond to acidosis (low blood pH)?
It increases bicarbonate reabsorption and hydrogen ion excretion
How does the urinary system respond to alkalosis (high blood pH)?
It decreases bicarbonate reabsorption and increases hydrogen ion reabsorption
What is the main force driving fluid movement between compartments in the body?
Osmotic pressure, largely determined by sodium concentrations
What is the role of the renal tubules in maintaining electrolyte balance?
They selectively reabsorb electrolytes and water, adjust their concentrations based on the body’s needs, and excrete the remainder in urine
