Question 34

[nathan.blu4013]

34) Which of the following does NOT occur during inspiration?

1. Increased pressure within the chest cavity[x]
2. Contraction of the rib cage muscles[x]
3. Downward displacement of the diaphragm [x]
4. Increased diameter of the chest [x]


How does option B occur during inspiration? If anything there is a relaxation of rib cage muscles....

[admin]

The rib cage (ie intercostal, inter means between and costal refers to ribs) muscles contract to: elevate the ribs thus increasing the volume of the thoracic cavity AND by firming up the chest wall thus preventing inward bellowing.

http://people.eku.edu/ritchisong/RITCHISO//301notes6.htm

http://www.normanallan.com/Sci/breath%20movement.htm

http://en.wikipedia.org/wiki/Muscles_of_respiration

[admin]

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