About how much weight will the average fetus gain during the last three months of gestation?

Every firing of a neuron produces an impulse of the same strength. This is called the ______

a. action potential b. all-or-none law c. threshold of excitation d. graded potential

Studies of preparedness and social phobia

A) provide an explanation for why such a maladaptive behavioral response persists. B) reveal that an explicit perception of threat is necessary to evoke a sympathetic response. C) do not provide justification for the seemingly irrational nature of social phobia. D) find that angry faces act as fear-relevant stimuli.