Which of the following is applicable to a change in the affinity of hemoglobin for oxygen?
1. Decreased in rapidly metabolizing tissues
2. Increased at higher than normal body temperatures
3. Increased at higher than normal blood 2,3-DPG levels
4. Decreased at more basic than normal blood pH
The part of the human brain where the main respiratory center is located is:
1. | pons varolii | 2. | cerebrum |
3. | medulla oblongata | 4. | thalamus |
The respiratory center in humans can be primarily stimulated by:
1. carbon dioxide and hydrogen ions
2. oxygen gas levels in the blood
3. oxygen gas levels in the hemoglobin
4. conscious feeling for the need for more oxygen
The peripheral chemoreceptors in carotid and aortic bodies respond to:
1. hydrogen ion concentration.
2. levels of carbon dioxide in the blood.
3. levels of oxygen in the blood.
4. all of the above
Why would hemoglobin deliver oxygen to the tissues?
1. oxygen concentration of tissue fluid is lower
2. carbon dioxide concentration of tissue fluid is lower
3. carbon dioxide concentration of tissue fluid is higher
4. the oxygen concentration of blood is lower
What is the state that describes the hemoglobinic acid?
1. | oxidized | 2. | hydrated |
3. | reduced | 4. | hyper |
Oxidized hemoglobin is known as:
1. carboxyhemoglobin
2. methemoglobin
3. oxy hemoglobin
4. carbaminohemoglobin
2,3-diphosphoglycerate in red blood cells:
1. enhances oxygen unloading at the systemic capillaries
2. makes deoxyhemoglobin less stable
3. shifts the oxyhemoglobin dissociation curve to the left
4. stimulates the production of more red blood cells
The external intercostal muscles and the diaphragm contract:
1. during inhalation
2. during exhalation
3. during both inhalation and exhalation
4. during neither inhalation nor exhalation.
Carbon dioxide is transported in blood by all the following mechanisms except:
1. bound to the protein portion of hemoglobin
2. bound to the iron atoms of hemoglobin
3. dissolved in plasma
4. as bicarbonate
All the following statements regarding hemoglobin are true except:
1. Hemoglobin loads up with oxygen in the alveolar capillaries.
2. Approximately 97% of hemoglobin in red blood cells is in the form of oxyhemoglobin.
3. Hemoglobin has a lower affinity for oxygen at higher temperatures.
4. Each molecule of hemoglobin can carry one molecule of oxygen.
When you hold your breath the urge to inhale first results from
1. rising PCO2
2. falling PCO2
3. rising PO2
4. falling PO2
The Bohr effect is a physiological phenomenon first described in 1904 by the Danish physiologist Christian Bohr. It explains why
1. hemoglobin binds carbon monoxide more readily than oxygen
2. hemoglobin unloads its oxygen when it encounters low pH
3. diffusion occurs so slowly over long distances
4. oxygen is present in the atmosphere in relatively low concentrations
The chloride shift is also known as Hamburger phenomenon and it
1. occurs primarily in pulmonary capillaries.
2. occurs when Cl- replace HCO3- within red blood cells.
3. decreases the formation of bicarbonate ions.
4. decreases the number of hydrogen ions.