Hyperkalemia can cause cardiac arrest. In response to hyperkalemia, the hormone secreted by human body and the site of its action are respectively:
1. aldosterone; distal tubule
2. aldosterone; proximal convoluted tubule
3. ADH; cortical collecting duct
4. ADH; proximal convoluted tubule

A substance freely filtered and then completely reabsorbed by the nephron is:
1. creatinine
2. inulin
3. para amino hippuric acid
4. glucose

Regarding the reabsorption of bicarbonate ions in the proximal convoluted tubule, the correct statement is:
1. The cuboidal brush bordered epithelium directly reabsorb bicarbonate ions.
2. The cells secrete H⁺ ions to reabsorb all of the filtered bicarbonate.
3. Carbonic anhydrase is not found in the PCT.
4. More bicarbonate is reabsorbed and less bicarbonate is excreted in alkalosis.

A substance is neither filtered, reabsorbed, nor secreted in the kidney. This substance would be most likely found in:
1. glomerular filtrate
2. blood in the renal vein
3. Collecting duct
4. Loop of Henle

What will be seen in a fish living in a marine environment?
1. They do not drink the water in their surroundings.
2. They drink the water in their surroundings.
3. They move monovalent ions into their bodies through active transport across their epithelial outer tissue.
4. They move monovalent ions out of their bodies through active transport across their epithelial outer tissue.

Sodium is the principal cation in blood. If the blood concentration of sodium ions gets below normal:
1. blood volume increases and blood pressure decreases
2. water drains from the collecting duct
3. blood volume and blood pressure decrease
4. ADH secretion increases

The urinary clearance of a substance is found to be less than its glomerular filtration rate. This substance most likely:
1. is filtered and is not subject to reabsorption or secretion
2. is filtered and is partially reabsorbed
3. is filtered and is partially secreted
4. is totally secreted

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

Which of the following contributes maximum to the buffer capacity of human body?
1. carbonic acid/bicarbonate buffer system.
2. phosphate buffer system.
3. protein buffer system.
4. oxygen/carbondioxide buffer system.

Patients with uncontrolled diabetes mellitus are most likely to develop complications like:
1. respiratory acidosis and retention of body fluid.
2. respiratory alkalosis and dehydration.
3. metabolic acidosis and dehydration.
4. metabolic alkalosis and dehydration.