Hummingbirds can hover because
A) They have large breast muscles that enable their wings to generate lift in the upstroke and downstroke.
B) They burn only sugar and not fat.
C) Their wings beat rapidly, often higher than 30 beats/sec.
D) A and C
Answer: D
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Terry suffers from dissociation of memories from their emotional content as the result of an automobile accident. What system of the brain is probably damaged?
A) the prefrontal lobe B) the general interpretive area C) the limbic system D) the preoptic area E) the reticular activating system
Which of the following is not a function of the respiratory system?
A. It allows exchange of oxygen and carbon dioxide between blood and air. B. It contributes to maintenance of pH balance. C. It helps to expel abdominal contents during defecation and childbirth. D. It helps to transport gases to tissues. E. It permits vocalizations.
In ruminants, heart girth and barrel make up _________________________________________
Fill in the blank(s) with correct word
Tear secretions are governed by parasympathetic fibers within which cranial nerve?
A. X B. III C. V D. VII E. IX