The ____ argues that activities during the day deplete key factors in our brain that must be replenished by sleeping

Scientists study stress by measuring many physical responses to stress. One thing they measure is the release of stress hormones called _____

Fill in the blank with correct word

A specific time during development when a particular event has its greatest consequences and the presence of certain kinds of environmental stimuli is necessary for development to proceed normally is called

a) discontinuous change. b) continuous change. c) critical period. d) natural change.