A hormone formed in the blood that causes vasoconstriction is:

1. Renin	2. Aldosterone
3. Angiotensin	4. Vasopressin

The collecting ducts become permeable to water and urea due to:

Identify the correct statement regarding human kidney function if ADH is not secreted in the body:

The urine examination of a person suspected of a kidney disorder is most likely to show the presence of:

Total body water in humans makes up between 45 to 75% of total body weight. About two thirds of this is:
1. Extracellular fluid
2. Interstitial fluid
3. Intracellular fluid
4. Plasma

Intracellular fluid:
1. has a lower concentration of potassium than extracellular fluid.
2. has a lower concentration of sodium ions than extracellular fluid.
3. does not remain in osmotic equilibrium.
4. has a higher concentration of calcium ions than extracellular fluid.

The principal cation in the extracellular fluid is:

Increased stretching of the atrial wall, due to increased atrial blood volume, stimulates the release of:

Serum potassium concentrations are the most potent stimulator of secretion of:
1. Aldosterone
2. Angiotensin II
3. ADH
4. Atrial natriuretic hormone

The humoral stimulus for the secretion of aldosterone is:
1. elevated blood ${\mathrm{Na}}^{+}$ ion levels.
2. decreased blood ${\mathrm{Cl}}^{-}$ ion levels.
3. elevated blood ${\mathrm{K}}^{+}$ ion levels.
4. decreased blood ${\mathrm{Ca}}^{2+}$ ion levels.