All of the following are air-filled bony cavities with openings into the nasal cavity (paranasal sinuses) EXCEPT the
A. sphenoid sinus.
B. ethmoidal air cells.
C. mastoid air cells.
D. maxillary sinus.
E. frontal sinus.
Answer: C. mastoid air cells.
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Which plane divides the body into anterior and posterior portions?
a) frontal b) sagittal c) transverse d) oblique e) midsagittal
Which wave in an electrocardiogram represents repolarization of the ventricles?
a) R wave b) T wave c) S wave d) P wave e) Q wave
A condition in which the blood urea concentration is abnormally high is __________.
Fill in the blank(s) with the appropriate word(s).
Cyanide poisoning quickly leads to death because it blocks the final cytochrome molecule in the electron transport system. Why is this blockage lethal?
A) All hydrogen ion pumps deactivate. B) NADH molecules cannot give off their electrons. C) FADH2 molecules cannot give off their electrons. D) Electrons cannot transfer to oxygen. E) Coenzyme Q disassociates and becomes nonfunctional.