The _____, a flap of cartilage acting like a lid over the larynx, lies over the entrance to the larynx.
A. uvula
B. epiglottis
C. tonsils
D. vocal cord
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The trachea is kept open by 16-20 C-shaped rings of cartilage separated by _____
A. blood tissue
B. muscle tissue
C. fibrous connective tissue
D. nervous tissue
At the end of the bronchioles are clusters of air sacs called______
A. alveolus
B. bronchiole
C. capillary
D. alveoli
Each lung is enveloped in a double-folded membrane called _____
A. pleura
B. skin
C. chest
D. mucous membrane
The outer layer of the pleura is called ______
A. parietal pleura
B. mediastinum
C. visceral pleura
D. diaphragm
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