John, a 72-year-old grandfather, had been smoking heavily for 24 years and had a persistent cough. A biopsy of his lung tissue revealed considerable amounts of carbon particles
How could this happen considering the natural cleaning mechanism of the respiratory system?
What will be an ideal response
The sweeping action of the ciliated epithelium is essential in order to propel inhaled dust and other debris out of the respiratory tract. Anything that inhibits this mechanism would allow foreign substances to remain in the tract, which may cause damage. Chemicals such as nicotine may inhibit the action of the cilia, allowing carbon particles found in smoke to reach the lungs.
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What is the function of tactile disc?
A. Mechanoreceptors for heavy touch B. Mechanoreceptors for light touch C. Mechanoreceptors for light touch that bends the hair D. Mechanoreceptors for deep pressure
When comparing slow fibers to fast fibers, slow fibers
A) take less time to reach peak tension. B) have much larger fiber diameters. C) generate much more tension. D) are lacking myoglobin. E) appear dark red.
In chewing a bite of apple, what actions are are you performing with your mandible?
A. Protraction and retraction B. Lateral and medial excursion C. Eversion and inversion D. Adduction and abduction E. Depression and elevation
Which of the following is a plane (gliding) joint?
A. Humeroscapular joint B. Atlanto-occipital joint C. Intercarpal joint D. Talocrural joint E. Sternoclavicular joint