Unit 3 Week 12 Quiz

Most of the carbon dioxide produced by humans is ________. A) converted to bicarbonate ions by carbonic anhydrase, an enzyme in red blood cells B) bound to hemoglobin C) transported in the erythrocytes as carbonic acid D) bicarbonate ions bound to hemoglobin

A) converted to bicarbonate ions by carbonic anhydrase, an enzyme in red blood cells

At the summit of a high mountain, the atmospheric pressure is 380 mm Hg. If the atmosphere is still composed of 21 percent oxygen, then the partial pressure of oxygen at this altitude is about ________. A) 0 mm Hg B) 80 mm Hg C) 160 mm Hg D) 380 mm Hg

B) 80 mm Hg

You are a physician, and you are seeing a patient who complains of abnormal fatigue during exercise. You find that the immediate problem is a buildup of carbon dioxide in the tissues. What is the most likely cause? A) Abnormally shaped platelets B) Abnormal carbonic anhydrase C) Abnormal hemoglobin D) Not enough hemoglobin

B) Abnormal carbonic anhydrase

The air pressure in Denver, Colorado, is about 83 percent of the air pressure in Miami Beach, which is at about sea level. Given that the air pressure in Miami Beach is 760 mm Hg and oxygen makes up 21 percent of the air in Miami Beach, what are the percentage of oxygen and the partial pressure of oxygen in Denver? A) 21%, 21mm Hg B) 21%; 132 mm Hg C) 17.4%; 132 mm Hg D) 17.4%; 21 mm Hg

C) 17.4%; 132 mm Hg

A rabbit taken from a meadow near sea level and moved to a meadow high on a mountainside would have some trouble breathing. Why? A) The percentage of oxygen in the air at high elevations is lower than at sea level B) The percentage of oxygen in the air at high elevations is higher than at sea level C) The partial pressure of oxygen in the air at high elevations is lower than at sea level. D) The partial pressure of oxygen in the air at high elevations is higher than at sea level.

C) The partial pressure of oxygen in the air at high elevations is lower than at sea level.

During exercise, neurons in contact with cerebrospinal fluid monitor pH and use this measure to control breathing. In this example, pH is altered by ____________ and the increase in breathing is an example of an ___________. A) CO2 binding hemoglobin, Sensor B) H+ generated by Carbonic Anhydrase, Integrator C) CO2 binding hemoglobin, Effector D) H+ generated by Carbonic Anhydrase, Effector E) CO2 dissolved in the blood, Integrator

D) H+ generated by Carbonic Anhydrase, Effector

In which location would you expect the oxygen concentration to be the lowest? A) The environment B) The blood C) The lungs D) Tissues

D) Tissues

Breathing is primarily regulated by ________. A) erythropoietin levels in the blood B) the concentration of red blood cells C) hemoglobin levels in the blood D) carbon dioxide concentration and pH sensors

D) carbon dioxide concentration and pH sensors