Question 1

If the thyroid and parathyroid glands are surgically removed,which of the following would go out of balance without replacement therapy?

Accepted Answer

The parathyroid glands play an important role in regulating calcium ion levels in the body. Without them, there would be a decrease in serum calcium levels, leading to hypocalcemia. Replacement therapy with calcium and vitamin D would be needed to manage this condition. Anion, sodium, and potassium ion levels are not directly regulated by the thyroid or parathyroid glands.

Question 2

Molecules that can act reversibly as acids or bases depending upon the pH of their environment are called ________.

Accepted Answer

Amphoteric molecules are able to act as both an acid or base depending on the pH of their environment. This is because they have both acidic and basic groups within their structure that can donate or accept protons as needed. Examples of amphoteric molecules include water and amino acids. The other choices are not related to the concept of reversible acid-base behavior.

Question 3

One of the major physiological factors that triggers thirst is ________.

Accepted Answer

A rise in plasma osmolality, which indicates a higher concentration of solutes in the blood, triggers thirst. This is because the body needs water to dilute the solutes and maintain homeostasis.

Question 4

The regulation of sodium ________.

Accepted Answer

The regulation of sodium is linked to blood pressure. Sodium is an electrolyte that plays a key role in controlling the volume of extracellular fluid in the body, which in turn affects blood pressure. When sodium levels are high, the body retains water to maintain a balance of electrolytes and blood volume, which can lead to increased blood pressure. Conversely, low sodium levels can lead to decreased blood pressure.

Answer: D
 The regulation of sodium involves aldosterone, a hormone that increases sodium excretion in the kidneys. Aldosterone is produced by the adrenal gland and acts on the kidneys to increase the reabsorption of sodium and the secretion of potassium, which helps to maintain electrolyte balance in the body. When sodium levels are low, aldosterone is released to signal the kidneys to retain more sodium and excrete more potassium, which helps to raise blood pressure and maintain proper electrolyte balance.

Question 5

Falling arterial blood pressure promotes ________.

Accepted Answer

Falling arterial blood pressure triggers mechanisms to increase blood pressure, including vasoconstriction, which narrows blood vessels to help increase blood pressure.

Question 6

What is the effect of acidosis on the body? Of alkalosis?

Accepted Answer

The answer of What is the effect of acidosis on...

Question 7

Which of the following is NOT a disorder of water balance?

Accepted Answer

Excessive hydration due to excess atrial natriuretic peptide (ANP) secretion is not a disorder of water balance. ANP is involved in reducing blood volume and blood pressure by increasing the excretion of sodium and water by the kidneys, not causing excessive hydration.

Question 8

Which of the following statements is true regarding fluid shifts?

Accepted Answer

Electrolytes have greater osmotic power due to their ability to dissociate into ions, which attracts water molecules through osmosis. This allows them to have a significant influence on fluid shifts. Nonelectrolytes, on the other hand, do not dissociate into ions and therefore have relatively low osmotic power. Proteins are important for regulating fluid balance, but they do not have as much of an impact on fluid shifts as electrolytes do. Option A is incorrect as there are solutions with more negative electrolytes than positive ones, and it is possible to follow fluid shifts. Option B is incorrect as nonelectrolytes have a relatively minor role in fluid shifts compared to electrolytes.

Question 9

A patient is breathing slowly and blood pH analysis indicates an abnormally high value.What is the likely diagnosis?

Accepted Answer

A slow respiratory rate would cause an increase in carbon dioxide retention, leading to respiratory acidosis. However, the question states that the blood pH is abnormally high, which contradicts respiratory acidosis. Therefore, the probable diagnosis is metabolic alkalosis where the relative excess of bicarbonate leads to an elevated blood pH.

Question 10

Mary finds that she regularly retains water at a certain point in the menstrual cycle.Which of the following is chemically similar to aldosterone,and like aldosterone,enhances NaCl reabsorption in the renal tubules?

Accepted Answer

The answer of Mary finds that she regularly retains water...

Question 11

After completing a marathon on a particularly warm day,Dave consumes four liters of water.Soon after,he begins to feel nauseous and starts vomiting.What is likely happening to Dave?

Accepted Answer

Dave is likely experiencing hyponatremia, which occurs when there is a very low extracellular sodium ion concentration in the body. This can happen after consuming excessive amounts of water in a short period, diluting the sodium in the body, leading to symptoms like nausea and vomiting.

Question 12

Blood analysis indicates a low pH,and the patient is breathing rapidly.Given your knowledge of acid-base balance,which of the following is most likely?

Accepted Answer

A low pH indicates acidosis, and rapid breathing (hyperventilation) is a compensatory mechanism to decrease CO2 levels, suggesting the primary problem is metabolic acidosis, not a respiratory issue.

Question 13

An illness causes Doug to experience severe diarrhea and an accompanying loss of bicarbonate-rich secretions.How can this metabolic acidosis be compensated?

Accepted Answer

Increased respiratory rate and depth can compensate for metabolic acidosis by expelling more carbon dioxide, which helps to decrease the acidity of the blood. This is known as respiratory compensation.

Option B is incorrect because increased renin secretion would activate the renin-angiotensin-aldosterone system, which would retain sodium ions and increase blood volume, leading to an increase in blood pressure.

Option C is incorrect since hypoventilation would lead to an increase in carbon dioxide retention, which would further exacerbate metabolic acidosis.

Option D is incorrect since enhanced sodium loss in urine would decrease blood volume, leading to a decrease in blood pressure, which would not help to compensate for metabolic acidosis.

Question 14

The most important force causing net outward water flow across capillary walls is ________.

Accepted Answer

The hydrostatic pressure of capillary blood is the most important force causing net outward water flow across capillary walls. This pressure is generated by the pumping action of the heart and the resistance of the blood vessels. This force pushes water out of the capillaries and into the interstitial fluid. The other pressures listed (intracellular hydrostatic pressure, hydrostatic pressure of interstitial fluid, and osmotic pressure of plasma proteins) may play a role in fluid movement, but they are not the primary force driving net outward flow across capillary walls.

Question 15

Annie has just eaten a large order of heavily salted French fries,some pickled eggs,and some cheese.How will consuming this much salt affect her physiology?

Accepted Answer

Consuming a large amount of salt will cause an increase in blood volume, which can lead to a temporary increase in blood pressure. This is because salt attracts water, and the extra water in the blood increases its volume. However, prolonged consumption of high levels of salt can have negative effects on blood pressure and kidney function. Options B and C are not correct, as there is no significant change in pH or osmolality in this scenario. Option D is also not correct, as hypotension (low blood pressure) is unlikely to occur as a result of consuming a large amount of salt.

Question 16

Which of the following hormones functions to increase water reabsorption by inserting aquaporins into the principal cell apical membranes?

Accepted Answer

Antidiuretic hormone (ADH) is also known as vasopressin and stimulates water reabsorption in the kidney tubules by inserting aquaporins into the principal cell apical membranes. This increases water permeability and facilitates water reabsorption. ADH is released by the posterior pituitary gland in response to changes in blood osmolarity and/or blood volume.

Question 17

What provides the shortest-term mechanism for preventing acid-base imbalances in the body? The longest-term mechanism?

Accepted Answer

The answer of What provides the shortest-term mechanism for preventing...

Question 18

Insufficient parathyroid hormone production in the body could result in ________.

Accepted Answer

The answer of Insufficient parathyroid hormone production in the body...

Question 19

Nancy is experiencing an acute panic attack.While hyperventilating,she remembers to open a paper bag and breathe into it.What is Nancy trying to prevent?

Accepted Answer

Nancy is trying to prevent respiratory alkalosis, which can occur as a result of hyperventilation during a panic attack. Breathing into a paper bag helps increase the carbon dioxide levels in her bloodstream, which counteracts the excessive elimination of carbon dioxide from hyperventilation and can help restore a more normal blood pH. Respiratory acidosis (A) and metabolic acidosis (B) occur when there is too much acid in the blood, while metabolic alkalosis (D) occurs when there is too much base in the blood.

Question 20

The maintenance of the proper pH of the body fluids may be the result of ________.

Accepted Answer

The control of respiratory ventilation, specifically the regulation of CO2 levels and elimination, is a major mechanism for maintaining proper pH of body fluids through the bicarbonate buffer system. Choices A, C, and D also contribute to pH regulation, but are not as significant as the control of respiratory ventilation.

Quiz 26: Fluid,electrolyte,and Acid-Base Balance