The doublet that results with more frequent stimulation of the frog heart represents _______.
A) an extra contraction of the ventricles
B) an extrasystole and an extra contraction of the atria
C) an extrasystole and an extra contraction of the ventricles
D) an extra contraction of the atria
E) an extrasystole
Answer: C) an extrasystole and an extra contraction of the ventricles
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Two standard measurements are used to determine fetal length. Which of these would be the longer of the two measurements on any normal fetus?
A. CHL B. HRL C. CFL D. CRL E. HTL
The hormone that dominates during the alarm phase of the general adaptation syndrome (GAS) is
A) testosterone. B) aldosterone. C) cortisol. D) thyroid hormone. E) epinephrine.
Which of the following choices is FALSE? The chromophore
A) Absorbs energy from photons. B) Is a derivative of vitamin D. C) Is covalently linked to a member of the opsin gene family. D) Plays a role in photoreceptor sensitivity to different colors.
Elderly persons may become less able to maintain stable body temperature because
A) their sebaceous glands become overactive. B) the skin becomes too oily. C) the number of sweat glands diminishes. D) they sweat excessively.