What balance do the kidneys maintain in the body?

What balance do the kidneys maintain in the body?

• A. Balance between water and salt in the body
• B. Balance between water and sugar in the body
• C. Maintain balance between salt in water in the body
• D. Balance between minerals and vitamins

Answer: (C)

The kidneys mainly regulate fluid and electrolyte balance—specifically the amount of water and salt (sodium and other electrolytes) in the body. They adjust how much water and salt are reabsorbed or excreted in the nephron, responding to hydration status, blood pressure, and hormones like vasopressin and aldosterone. This keeps blood volume, blood pressure, and the body’s osmolarity (the concentration of particles in the blood) in a stable range, which is essential for proper cell function and overall homeostasis. Among the options, the statement that describes balancing water and salt in the body best captures this core kidney function. The idea of balancing water with sugar isn’t the kidneys’ primary role, and minerals with vitamins aren’t the key focus of renal fluid-electrolyte regulation; the phrasing about salt in water is related but less precise than the standard focus on water–salt balance.

The kidneys mainly regulate fluid and electrolyte balance—specifically the amount of water and salt (sodium and other electrolytes) in the body. They adjust how much water and salt are reabsorbed or excreted in the nephron, responding to hydration status, blood pressure, and hormones like vasopressin and aldosterone. This keeps blood volume, blood pressure, and the body’s osmolarity (the concentration of particles in the blood) in a stable range, which is essential for proper cell function and overall homeostasis. Among the options, the statement that describes balancing water and salt in the body best captures this core kidney function. The idea of balancing water with sugar isn’t the kidneys’ primary role, and minerals with vitamins aren’t the key focus of renal fluid-electrolyte regulation; the phrasing about salt in water is related but less precise than the standard focus on water–salt balance.