Question 1

The presence of ________ in the urine is an early indicator that tubular secretion is not functioning correctly.

Accepted Answer

The presence of uric acid in the urine,is an early indicator that tubular secretion is not functioning correctly.

Question 2

The optimal blood pH range is between 7.34 and 7.45.

Accepted Answer

The normal pH of arterial blood is around 7.4.Therefore,a person is said to have acidosis when the blood pH is below 7.34 and alkalosis when the blood pH is higher than 7.45.

Question 3

If the blood is alkaline:

Accepted Answer

If the blood is basic,hydrogen ions are not excreted,and bicarbonate ions are not reabsorbed.

Question 4

If you were a doctor and had a patient who was suffering from water intoxication (drinking too much water),which of the following treatments would you administer in order to bring his body back into homeostasis?

Accepted Answer

The kidneys will excrete salt from the body,and water will follow.

Question 5

Which element is not part of the nitrogenous waste products produced by animals?

Accepted Answer

Ammonia contains nitrogen and hydrogen.Urea and uric acid both contain carbon,hydrogen,nitrogen and oxygen.Phosphorous is not found in any of the three nitrogenous waste products produced by animals.

Question 6

If precipitates have built up forming a blockage in the ureter,what is the correct order of structures that will be blocked due to back filling of fluids?

Accepted Answer

If the blockage occurred in the ureter,fluid would start back filling in the following order: ureter - renal pelvis - collecting duct - distal convoluted tubule - loop of Henle - proximal convoluted tubule - glomerular capsule

Question 7

What is the relationship between water needed for the excretion of urine and the energy required to produce urine?

Accepted Answer

The less water available the more energy needed for urine formation.If there is a large amount of water available then there is less need for energy to produce urine

Question 8

The loop of of the nephron will exhibit:

Accepted Answer

Salt passively diffuses out of the lower portion of the ascending limb of the loop of the nephron,but the upper,thick portion of the limb actively extrudes NaCl into the tissue of the outer renal medulla.See Figure 34.5A.

Question 9

When renin is released it will eventually:

Accepted Answer

Renin is an enzyme that changes angiotensinogen (a large plasma protein produced by the liver)into angiotensin I.Later,angiotensin I is converted to angiotensin II,a powerful vasoconstrictor that also stimulates the adrenal glands,which lie on top of the kidneys,to release aldosterone.Aldosterone is a hormone that promotes the excretion of potassium ions (K+)and the reabsorption of sodium ions (Na+)at the distal convoluted tubule.The reabsorption of sodium ions is followed by the reabsorption of water.Therefore,blood volume and blood pressure increase.See Figure 34.5B.

Question 10

Which hormone from the adrenal cortex will cause the distal convoluted tubules to reabsorb more sodium ions?

Accepted Answer

Aldosterone is a hormone that promotes the excretion of potassium ions (K+)and the reabsorption of sodium ions (Na+)at the distal convoluted tubule.Aldosterone is produced by the adrenal cortex.See Figure 34.5B.

Question 11

Which body system does the bicarbonate buffer system work together with in order to maintain the pH of the blood?

Accepted Answer

The bicarbonate ion (HCO3F1F1F1S1F1F1F10)buffer system works together with the breathing process to maintain the pH of the blood.

Question 12

The hormone which is responsible for the reabsorption of water is:

Accepted Answer

Antidiuretic hormone (ADH),released by the posterior lobe of the pituitary gland,plays a role in water reabsorption at the collecting duct.

Question 13

A biologist is studying the site in the nephron where most of the water and salt is reabsorbed back into the bloodstream.Based on this information,you would conclude that he or she is studying which of the following?

Accepted Answer

Along with nutrients,most of the water and salt (NaCl)present in the filtrate is reabsorbed across the wall of the proximal convoluted tubule.

Question 14

How can urine contain a higher concentration of wastes (be hypertonic)than the blood?

Accepted Answer

The processes of tubular resabsorption and tubular secretion ensure that urine contains more waste molecules than blood.

Question 15

The second way substances are removed from the blood and are added to the tubular fluid is:

Accepted Answer

Tubular secretion is the second way substances are removed from blood and added to tubular fluid.Substances such as uric acid,hydrogen ions,ammonia,creatinine,histamine,and penicillin are eliminated by tubular secretion.The process of tubular secretion helps rid the body of potentially harmful compounds that were not filtered into the glomerulus.See Figure 34.4.

Question 16

The presence of which of the following,in high concentrations in the urine,would indicate that an individual is diabetic?

Accepted Answer

If there is more glucose in the filtrate than there are carriers to handle it,glucose will exceed its renal threshold,or transport maximum.When this happens,the excess glucose in the filtrate appears in the urine.People with diabetes mellitus have an abnormally large amount of glucose in the blood and filtrate because the liver fails to store glucose as glycogen.

Question 17

If a person is experiencing kidney failure and is unable to secrete renin,what cascade of events are they likely to experience?

Accepted Answer

Renin is an enzyme that changes angiotensinogen (a large plasma protein produced by the liver)into angiotensin I.Later,angiotensin I is converted to angiotensin II,a powerful vasoconstrictor that also stimulates the adrenal glands,which lie on top of the kidneys,to release aldosterone (Fig.34.5B).Aldosterone is a hormone that promotes the excretion of potassium ions (K+)and the reabsorption of sodium ions (Na+)at the distal convoluted tubule.The reabsorption of sodium ions is followed by the reabsorption of water.Therefore,blood volume and blood pressure increase.If renin is not available,then none of these events will occur.

Quiz 34: Osmoregulation and Excretion