ANSWER ALL QUESTIONS. If not please dont bother thanks. 21. Which of the followi
ID: 181157 • Letter: A
Question
ANSWER ALL QUESTIONS. If not please dont bother thanks.
21. Which of the following areas of the brain is believed to be the location of the “pacemaker” for breathing?
A. DRG
B. Hypothalamaus
C. Pneumotaxic center
D. Pons
E. Medulla
22. Compare the changes in percent to hemoglobin saturation that would occur in the two following situations:
I. The blood Po2 drops from 100 mm Hg to 80 mm Hg.
II. The blood Po2 drops from 40 mm Hg to 20 mm Hg.
A. In both situation, the percent hemoglobin saturation would decrease 20%
B. There would be a large reduction in percent hemoglobin saturation in situation I but very little reduction in Situation II
C. There would be very little reduction in percent hemoglobin saturation in situation I but a large reduction in situation II
D. In Both sitatuion, the percent hemoglobin saturation would increase
23. Which of the following statements about hemoglobin is NOT true?
A. The plateau of the oxygen-hemoglobin curve is in. the blood PO2 range that exist in the lungs
B. Hemoglobin removes dissolved oxygen from the blood, thereby keeping PO2 low and allowing net diffusion of xygen from the airways to continue until the hemoglobin is close to saturated.
C. Hemoglobin holds onto more O2 IN THE PRESENCE OF CO2
D. Hemoglobin is found only in red blood cells
E.
Explanation / Answer
21.D and E.
Respratory centre in brain is located in pons and medulla oblongata. They respond to neural, chemical and harminal signals.
22.A
The oxyhaemoglobin curve is sigmoidal. There would be proportional decrease in percent hemoglobin saturation.
23.C.
Haemoglobin releases oxygen in the presence of more CO2. This helps in exchange of gases.