29) The function of the hepatic portal circulation is to: A) return glucose to the general circulation when blood sugar is low. B) collect absorbed nutrients for metabolic processing or storage before releasing them to the circulation for cellular use. C) carry toxins to the venous system for disposal through the urinary tract. D) distribute hormones. 30) True or False: Contraction of the external intercostals normally accompanies inspiration. A) True B) False 31) Which of the following regions of the nephron is most likely to be found in the renal medulla? A) distal convoluted tubule C) proximal convoluted tubule B) loop of Henle D) glomerulus 32) An increase in the permeability of the cells of the collecting tubule to water is due to: A) a decrease in the production of ADH. B) an increase in the production of aldosterone. C) an increase in the production of ADH. D) a decrease in the concentration of the blood plasma. 33) The kidneys are stimulated to produce renin: A) by a decrease in the blood pressure. B) when the peritubular capillaries are dilated. C) when the specific gravity of urine rises above 1.10. D) when the pH of the urine decreases. 34) The fatty tissue surrounding the kidneys is important because: A) it stabilizes the position of the kidneys by holding them in their normal position. B) it ensures adequate energy for the adrenal glands to operate efficiently. C) it is necessary as a barrier between the adrenal glands and kidneys. D) Actually, it is not important and in fact can be a detriment to the kidneys. 35) Excretion of dilute urine requires: A) relative permeability of the distal tubule to water. B) transport of sodium and chloride ions out of the descending loop of Henle. C) impermeability of the collecting tubule to water. D) the presence of ADH.