1. Which of the following statements about surface tension is false?
You correctly answered: c. Surface tension acts to increase the size of the alveoli within the lungs.
2. Which of the following statements about surfactants is false?
You correctly answered: d. Surfactant works by increasing the attraction of water molecules to each other.
3. Just before an inspiration begins, the pressure within the intrapleural cavity You correctly answered: b. is less than the pressure within the alveoli.
4. The respiratory condition of pneumothorax refers to You correctly answered: c. any opening that equalizes the intrapleural pressure with the atmospheric pressure.
5. A pneumothorax can lead to You correctly answered: b. atelectasis.
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Experiment Results
Predict Question:
Predict Question 1: What effect will adding more surfactant have on these lungs?
Your answer : b. Airflows will further increase.
Predict Question 2: What will happen to the collapsed lung in the left side of the glass bell jar if you close the valve?
Your answer : c. The lung will remain collapsed.
Stop & Think Questions:
Why did the sequential additions of surfactant change this lung system?
You correctly answered: a. Surface tension was sequentially decreased.
Premature infants often have difficulty breathing because the amount of surfactant in their lungs is You correctly answered: b. too low.
What happened to the left side of the bell jar when the valve was opened?
You correctly answered: b. The intrapleural pressure equalized with the atmospheric pressure.
Did the collapsed left lung reinflate?
You correctly answered: b. No, it did not.
Experiment Data:
Radius Breath Rate Surfactant Pressure Left Pressure Right Flow Left Flow Right Total Flow
5 15 0 -4 -4 49. 69 49. 69 99. 38
5 15 2 -4 -4 69. 56 69. 56 139. 13
5 15 4 -4 -4 89. 44 89. 44 178. 88
5 15 0 -4 -4 49. 69 49. 69 99. 38
5 15 0 0. 00 -4 0. 00 49. 69 49. 69
5 15 0 0. 00 -4 0. 00 49. 69 49. 69
5 15 0 -4 -4 49. 69 49. 69 99. 38
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Post-lab Quiz Results
You scored 100% by answering 4 out of 4 questions correctly.
1. The addition of surfactant to the lung interior You correctly answered: c. increa...
