Exam 48: Gas Exchange

Refer to the graph. When you are exercising hard, you are producing more CO₂ in your muscles than you are when resting.This causes a shift in the oxygen-binding/dissociation curve of your hemoglobin, with the new curve looking like the curve labeled _______ in the graph.

Air is about 78% nitrogen, and atmospheric pressure is about 760 mm Hg at sea level.The partial pressure of nitrogen at sea level is about _______ mm Hg.

_______ is a condition in which respiratory problems result from inflammation that destroys the alveoli and leads to large, but few, alveoli.It is caused primarily by smoking and is a leading cause of death in the United States.

Which statement about gill ventilation in fishes is false?

Electrophysiological recordings are made to determine the activity of respiratory motor neurons from a patient's medulla.The recordings show that the respiratory motor neurons from the dorsal medulla are functioning normally, but those from the ventral medulla have lower than normal activity.Which is the patient's most likely symptom?

One reason rapid gas exchange can be accomplished more easily in air than in water is that

If you climb a mountain to an altitude where the PO₂ is half of what it is at sea level, it is likely that

By converting CO₂ to H₂CO₃, carbonic anhydrase _______the PCO₂ in endothelial cells, red blood cells, and plasma, thereby _______ diffusion of CO₂ from tissue cells to these locations.

Which statement about the human respiratory system is true?

Which statement about positive cooperativity of hemoglobin is true?

Sensors for detecting PO₂ levels are found on two major arteries: the _______ and the carotid arteries.

Chemosensitive cells in the carotid bodies and aortic bodies are sensitive to the _______.When this falls, signals are sent to the medulla and cause a(n) _______ ventilation rate.This represents a _______ feedback control of breathing.

Respiratory gases are exchanged between the body fluids of an animal and its environment by

In humans, the process of exhalation is brought about in large part by

The notation PO₂ stands for the _______ of oxygen.

The presence of CO₂ in blood will lower blood pH because CO₂ combines with _______ to form _______.The rate of the reaction is increased by _______.

The lungs of _______ are the most efficient lungs of vertebrates.

Which feature characterizes carotid and aortic bodies?

In humans, the lower (posterior) side of the thoracic cavity is defined by the

Oxygen can be exchanged more easily in air than in water in part because