Chapter 42 Gas exchange Final
During most daily activities, the human respiration rate is most closely linked to the blood levels of _____
carbon dioxide
An decrease from pH 7.4 to pH 7.2 causes hemoglobin to _____.
increase its binding of H+
Which of the following is not a result of the decrease in blood pH? (do not know).
The affinity of hemoglobin for O2 increases.
The sun shining on a tidal pool during a hot day heats the water. As some water evaporates, the pool becomes saltier, causing _____.
a decrease in its oxygen content
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?
abnormal carbonic anhydrase
Most of the carbon dioxide produced by humans is _____.
converted to bicarbonate ions by an enzyme in red blood cells
To become bound to hemoglobin for transport in a mammal, atmospheric molecules of oxygen must cross _____.
five membranes—in and out of the cell lining the lung, in and out of the endothelial cell lining an alveolar capillary, and into the red blood cell—to bind with hemoglobin
Compared with the interstitial fluid that bathes active muscle cells, blood reaching these muscle cells in arteries has a _____.
higher P O2
Some human infants, especially those born prematurely, suffer serious respiratory failure because of _____.
lung collapse due to inadequate production of surfactant
Carbon dioxide levels in the blood and cerebrospinal fluid affect pH. This enables the organism to sense a disturbance in gas levels as _____.
the medulla oblongata, which is in contact with cerebrospinal fluid, monitors pH and uses this measure to control breathing
If a molecule of carbon dioxide released into the blood in your left toe is exhaled from your nose, it must pass through all of the following EXCEPT _____.
the pulmonary vein
What is another expression for the tidal volume during maximal inhalation and exhalation?
vital capacity
