The nature-versus-nurture debate with regard to intelligence is complicated because genetically determined traits have both ____ and ____ impacts on children's behaviors and resulting environments

The concordance rate for homosexuality in male identical twins is about

(a) .01% (b) .1% (c) 1 - 5% (d) 50%

When positively charged ions flow into a neuron and depolarize it, they create ______

a. a relative refractory period b. breakdown of the cell nucleus c. an action potential d. internal combustion