PhysioEx 10

Describe what happened to the pH and the carbon dioxide levels during rebreathing. How well did the results compare with your prediction?

My prediction was correct. During rebreathing pH decreased and PCO2 levels increased.

Describe what happened to the concentration of ions in the urine when the PCO2 was raised. How well did the results compare with your prediction?

My prediction was correct. When PCO2 was raised, the [H+] concentration in urine increased and the [HCO3-] concentration in urine decreased.

What condition was simulated when the PCO2 was raised?

Respiratory acidosis was the simulation condition when PCO2 was raised. This is because respiratory acidosis is caused by the accumulation of carbon dioxide in the blood.

What was the effect of returning to normal breathing after hyperventilation? a. The peak size did not increase during the second hyperventilation b. The breathing stopped temporarily to retain carbon dioxide c. The minimum PCO2 decreased more d. The maximum pH increased more

b. The breathing stopped temporarily to retain carbon dioxide

Hyperventilation results in a. respiratory acidosis b. respiratory alkalosis c. renal acidosis d. renal alkalosis

b. respiratory alkalosis

Were the pH and PCO2 in the normal range? a. pH was in the normal range but PCO2 was not b. pH was not in the normal range but PCO2 was c. Both pH and PCO2 were in the normal range

c. Both pH and PCO2 were in the normal range

Which of the following can cause respiratory acidosis? a. hyperventilation b. traveling to high altitude c. airway obstruction d. panic attack

c. airway obstruction

Which of the following is true of respiratory acidosis? a. hyperventilation is the cause b. the pH of the blood is above 7.45 c. the amount of carbon dioxide in the blood is greater than normal d. it is usually caused by traveling to high altitude

c. the amount of carbon dioxide in the blood is greater than normal

The fastest compensatory mechanism for maintaining pH homeostasis in the human body is a. the renal system b. the respiratory system c. the chemical buffering system d. the endocrine system

c. the chemical buffering system

Can the renal system fully compensate for acidosis or alkalosis? a. Yes, but only for respiratory acidosis b. Yes, but only for respiratory alkalosis c. Yes, both for respiratory alkalosis and respiratory acidosis d. No, neither for respiratory alkalosis nor respiratory acidosis

d. No, neither for respiratory alkalosis nor respiratory acidosis

What type of breathing results in acidosis? a. hyperventilation b. hypoventilation c. rebreathing d. hypoventilation and rebreathing

d. hypoventilation and rebreathing

Which of the following values increased with decreased metabolism? a. [H+] b. [HCO3-] c. pH d. pH and [HCO3-]

d. pH and [HCO3-]

What happened to the breathing when metabolism was increased? a. the breaths per minute decreased b. the breaths per minute increased c. the tidal volume increased d. the breaths per minute and the tidal volume increased

d. the breaths per minute and the tidal volume increased

Describe what happened to the blood pH when the metabolic rate was increased to 80 kcal/hr. What body system was compensating? How well did the results compare with your prediction?

My prediction was correct. When the metabolic rate was increased to 80 kcal/hr, the blood pH decreased and metabolic acidosis occurred. The respiratory system compensated by increasing breaths per minute.

Describe what happened to the pH and the carbon dioxide level with hyperventilation. How well did the results compare with your prediction?

My prediction was half way correct. During hyperventilation, pH increased and PCO2 decreased.

Explain how the renal system would compensate for respiratory acidosis.

The renal system would compensate for respiratory acidosis by excreting H+ ions and retaining bicarbonate ions.

In uncompensated respiratory alkalosis, the a. carbon dioxide levels of the blood are elevated b. carbon dioxide levels of the blood are low c. carbon dioxide level of the blood is normal d. pH of the blood is low

b. carbon dioxide levels of the blood are low

Which of the following is not a cause of metabolic acidosis? a. diabetes mellitus b. constipation c. diarrhea d. strenuous exercise

b. constipation

With renal compensation for respiratory acidosis, the pH of the urine a. increased because [H+] increased b. decreased because [H+] increased c. increased because [H+] decreased d. decreased because [H+] decreased

b. decreased because [H+] increased

The renal system can compensate for respiratory acidosis by a. retaining H+ and excreting bicarbonate ion b. excreting H+ and retaining bicarbonate ion c. retaining H+ and bicarbonate ion d. excreting H+ and bicarbonate ion

b. excreting H+ and retaining bicarbonate ion

Rebreathing a. simulates hyperventilation b. is exemplified by breathing into a paper bag c. results in the accumulation of oxygen d. results in respiratory alkalosis

b. is exemplified by breathing into a paper bag

Which of the following decreases the rate of metabolism? a. fever b. lowered body temperature c. stress d. eating food

b. lowered body temperature

The amount of carbon dioxide in the blood is measured in a. pH units b. mm Hg c. ml d. nanomoles

b. mm Hg

The functional unit of the kidneys is the a. neuron b. nephron c. glomerulus d. bladder

b. nephron

What do you think will happen to the pH and PCO2 levels during rebreathing? a. pH and PCO2 will decrease b. pH will decrease and PCO2 will increase c. pH will increase and PCO2 will decrease d. pH and PCO2 will increase

b. pH will decrease and PCO2 will increase

The condition you just simulated is a. respiratory acidosis caused by hypoventilation b. respiratory alkalosis caused by hyperventilation c. respiratory acidosis caused by hyperventilation d. respiratory alkalosis caused by hypoventilation

b. respiratory alkalosis caused by hyperventilation

The kidneys can compensate for respiratory alkalosis by a. excreting H+ and excreting bicarbonate ion b. retaining H+ and excreting bicarbonate ion c. retaining H+ and retaining bicarbonate ion c. excreting carbonic acid

b. retaining H+ and excreting bicarbonate ion

The tidal volume and breaths per minute increased with increased metabolism because a. the body temperature increased b. there is more carbon dioxide being formed c. the blood pH has increased

b. there is more carbon dioxide being formed

An increase in hydrogen ion concentration would a. increase pH b. increase buffering c. increase alkalinity d. decrease pH

d. decrease pH

Which of the following is not a potential cause of respiratory alkalosis? a. hyperventilation due to a panic attack b. traveling to high altitude c. hyperventilation due to anxiety d. emphysema

d. emphysema

Explain how returning to normal breathing after hyperventilation differed from hyperventilation without returning to normal breathing.

Returning to normal breathing after hyperventilation caused the min. PCO2 and min. pH to decrease and max. pH to increase. Hyperventilation without returning to normal breathing caused min. PCO2 to decrease, min. pH to stay the same, and max. pH to increase. This is because hyperventilation causes carbon dioxide to be removed from the blood faster than it is being produced by the body's cells. The body needs some time to replenish the CO2 that's been lost in order to return to normal.

List and describe some possible causes of metabolic acidosis.

Some possible causes of metabolic acidosis are ketoacidosis, salicylate poisoning, the ingestion of too much alcohol, diarrhea, and strenuous exercise.

List and describe some possible causes of metabolic alkalosis.

Some possible causes of metabolic alkalosis are ingestion of alkali, vomiting, and constipation.

Describe some possible causes of respiratory acidosis.

Some possible causes of respiratory acidosis are airway obstruction, depression of the respiratory center in the brain stem, lung disease (emphysema or chronic bronchitis), and drug overdose.

Describe some possible causes of respiratory alkalosis.

Some possible causes of respiratory alkalosis are traveling to high altitude (where the air contains less oxygen), or hyperventilation due to fever, panic attack, or anxiety.

Describe the normal ranges for pH and carbon dioxide in the blood.

The normal range for pH is between 7.35 and 7.45 and the normal range for PCO2 is between 35 and 45 mm Hg.

Describe what happened to the concentration of ions in the urine when the PCO2 was lowered. How well did the results compare with your prediction?

When lowering the PCO2, the [H+] concentration in urine decreased, and the [HCO3-] concentration in urine increased. My prediction was correct.

What condition was simulated when the PCO2 was lowered?

When the PCO2 was lowered, the simulated condition was respiratory alkalosis. This is because respiratory alkalosis is caused by a depletion of carbon dioxide.

Describe what happened to the blood pH when the metabolic rate was decreased to 20 kcal/hr. What body system was compensating? How well did the results compare with your prediction?

When the metabolic rate was decreased to 20 kcal/hr, blood pH increased and breaths per minute decreased. My prediction was correct. The respiratory system compensated by decreasing the breaths per minute.

If PCO2 in the blood increases, then a. [H+] increases and pH decreases b. [H+] decreases and pH decreases c. [H+] decreases and pH increases d. [H+] increases and pH increases

a. [H+] increases and pH decreases

With hyperventilation, the higher peaks on the tracing indicate a. a larger volume of air b. holding one's breath c. asthma d. elevated carbon dioxide in the blood

a. a larger volume of air

Carbon dioxide and water form a. carbonic acid (a weak acid) b. carbonic acid (a strong acid) c. carbonic acid (a weak base) d. carbonic acid (a strong base)

a. carbonic acid (a weak acid)

The reaction of water and carbon dioxide is catalyzed by a. carbonic anhydrase b. carbonic acid c. bicarbonate ion d. a buffer

a. carbonic anhydrase

Rebreathing simulates a. hypoventilation and respiratory acidosis b. hyperventilation and respiratory acidosis c. hypoventilation and respiratory alkalosis d. hyperventilation and respiratory alkalosis

a. hypoventilation and respiratory acidosis

What do you think will happen when the metabolic rate is increased to 80 kcal/hr? a. metabolic acidosis b. metabolic alkalosis c. respiratory acidosis d. respiratory alkalosis

a. metabolic acidosis

An increase in metabolic rate (without compensation) would result in a. more carbon dioxide in the blood b. less carbon dioxide in the blood c. respiratory acidosis d. respiratory alkalosis

a. more carbon dioxide in the blood

What do you think will happen to the pH and PCO2 levels with hyperventilation? a. pH and PCO2 will decrease b. pH will decrease and PCO2 will increase c. pH will increase and PCO2 will decrease d. pH and PCO2 will increase

a. pH and PCO2 will decrease

Respiratory alkalosis is characterized by a. pH greater than 7.45 and PCO2 less than 35 mm Hg b. pH greater than 7.45 and PCO2 greater than 35 mm Hg c. pH less than 7.35 and PCO2 greater than 45 mm Hg d. pH less than 7.35 and PCO2 less than 45 mm Hg

a. pH greater than 7.45 and PCO2 less than 35 mm Hg

When adjusting the controls, what happens to the blood pH when you lower the PCO2? a. the pH increases b. the pH decreases c. the pH stayed the same

a. the pH increases

What effect do you think raising the PCO2 will have on [H+] and [HCO3-] in the urine? a. [H+] and [HCO3-] will increase b. [H+] and [HCO3-] will decrease c. [H+] will increase and [HCO3-] will decrease d. [H+] will decrease and [HCO3-] will increase

c. [H+] will increase and [HCO3-] will decrease

Hypoventilation results in a. respiratory alkalosis b. a blood pH of >7.45 c. an accumulation of carbon dioxide in the blood d. rebreathing

c. an accumulation of carbon dioxide in the blood

In cases of acidosis, the pH of the blood is a. any acidic pH b. greater than 7.35 c. less than 7.35 d. less than 7.45

c. less than 7.35

Excessive vomiting results in a. loss of base, metabolic alkalosis b. loss of base, metabolic acidosis c. loss of acid, metabolic alkalosis d. loss of acid, metabolic acidosis

c. loss of acid, metabolic alkalosis

Respiratory acidosis is characterized by a. pH greater than 7.45 and PCO2 less than 35 mm Hg b. pH greater than 7.45 and PCO2 greater than 35 mm Hg c. pH less than 7.35 and PCO2 greater than 45 mm Hg d. pH less than 7.35 and PCO2 less than 45 mm Hg

c. pH less than 7.35 and PCO2 greater than 45 mm Hg

Which body system is compensating for the metabolic alkalosis? a. urinary b. cardiovascular c. respiratory d. digestive

c. respiratory

What effect do you think lowering the PCO2 will have on [H+] and [HCO3-] in the urine? a. [H+] and [HCO3-] will increase b. [H+] and [HCO3-] will decrease c. [H+] will increase and [HCO3-] will decrease d. [H+] will decrease and [HCO3-] will increase

d. [H+] will decrease and [HCO3-] will increase

Respiratory acidosis can be caused by all of the following except a. hypoventilation b. emphysema c. drug overdose d. an anxiety attack

d. an anxiety attack

Which of the following is not acidic? a. ketone bodies b. metabolic by-products of alcohol ingestion c. salicylate from aspirin d. antacids

d. antacids

The renal system compensates for a. chemical buffering systems b. respiratory acidosis c. respiratory alkalosis d. both respiratory acidosis and respiratory alkalosis

d. both respiratory acidosis and respiratory alkalosis

What do you think will happen when the metabolic rate is decreased to 20 kcal/hr? a. ph will decrease b. PCO2 will increase c. H+ will increase d. breaths per minute will decrease

d. breaths per minute will decrease