Lecture 26: Regulation of Respiration

Question 1

What respiratory center establishes the RAMP signal?

Answer 1

Dorsal respiratory group (DRG)

Question 2

What is the usual method of controlling respiratory rate?

Answer 2

Controlling the limiting point at which the RAMP signal suddenly ceases; the earlier the RAMP signal ceases, the shorter the duration of inspiration/expiration

Question 3

What respiratory center turns off the RAMP signal?

Answer 3

Pneumotaxic center (PRG)

Question 4

Slow-adapting pulmonary stretch receptors

Answer 4

Located in airway and sensitive to stretch; signals to vagus nerve and medulla to terminate inspiration/prolong expiration
Controls respiration in adults and infants during exercise

Question 5

Rapidly-adapting pulmonary stretch receptors/Mechanoreceptors

Answer 5

Located in airway, sensitive to irritation, foreign bodies, and stretch
Sent signals to vagus nerve then brain and elicits cough; powerful enough to override normal respiratory control

Question 6

J-receptors

Answer 6

Sensory endings in alveolar wall in juxtaposition to pulmonary capillaries
Sensitive to pulmonary edema, sends signals to vagus nerves then brain to elicit cough, tachypnea
Powerful enough to override normal respiratory control

Question 7

True of False: Acidosis occurs when the ratio of bicarbonate ion to carbon dioxide ion in the extracellular fluid decreases. When this change is due to a decrease in bicarbonate ion, it is called respiratory acidosis.

Answer 7

False

Question 8

The volume by which the lungs and thorax increase for each unit of pressure change in the transpulmonary pressure is referred to as:

A. Tidal Volume
B. Inspiratory Pressure
C. Compliance
D. Transpulmonary Pressure
E. Elasticity

Answer 8

C. Compliance

Question 9

During heavy exercise, blood flow through the lungs increases 4-7x that at rest. This increase is due to which of the following?

A. Increase in the number of open capillaries up to three times normal
B. Distension of capillaries and a doubling in flow rate
C. Increase in pulmonary arterial pressure
D. All of the above
E. A and B only

Answer 9

D. All of the above

Question 10

The Va/Q ratio is zero under which of the following conditions?

A. Va=infinity, Q=1
B. Va=infinity, Q=0
C. Va=0, perfusion>0
D. Va>0, Q=0

Answer 10

C. Va=0, perfusion > 0

Question 11

According to the O2-Hb dissociation curve, an increase in blood partial oxygen pressure will have which of the following effects?

A. A decrease in bound oxygen
B. An increase in bound oxygen
C. No change in bound oxygen
D. No correlation between the two variables

Answer 11

B. An increase in bound oxygen

Question 12

One gram of hemoglobin can bind how much oxygen?

A. 19.4 ml
B. 15.4 ml
C. 3.25 ml
D. 1.34 ml

Answer 12

D. 1.34 ml oxygen