Vasopressin causes
A)increased water reabsorption in the collecting duct
B)decreased sodium reabsorption in the PCT
C)rapid filling of the ventricles
D)inhibition of NaCl co - transport e)relaxation of the efferent arteriole
A) increased water reabsorption in the collecting duct
Vasopressin, also known as antidiuretic hormone (ADH), has several effects in the body. Let's go through each option and see which one is caused by vasopressin.
A) Increased water reabsorption in the collecting duct: This is correct. Vasopressin acts on the collecting ducts in the kidneys to increase the reabsorption of water, leading to concentrated urine.
B) Decreased sodium reabsorption in the PCT: This is incorrect. Vasopressin does not directly affect sodium reabsorption in the proximal convoluted tubule (PCT).
C) Rapid filling of the ventricles: This is incorrect. Vasopressin does not have any effect on the filling of ventricles in the heart.
D) Inhibition of NaCl co-transport: This is incorrect. Vasopressin does not inhibit the co-transport of sodium and chloride ions.
E) Relaxation of the efferent arteriole: This is also incorrect. Vasopressin has a vasoconstrictive effect on blood vessels, including the efferent arteriole, leading to increased blood pressure.
Therefore, the correct answer is A) increased water reabsorption in the collecting duct.