The fact that exposure to a teratogen during the period of the zygote often leads to a spontaneous abortion (miscarriage) while the same exposure during the period of the fetus can lead to minor defects of bodily structures or systems demonstrates that
a. the impact of teratogens depends on the genotype of the organism
b. the impact of teratogens changes the course of prenatal development
c. different teratogens affect different aspects of prenatal development
d. the impact of a teratogen depends on the amount, or dose, of the teratogen
Question 2
One reason why children might associate more with peers of their own sex is because they
a. may be more likely to share similar play styles.
b. see more same-sex friendships represented on children's television programs.
c. are taught by their parents to show such a preference.
d. have a biological preference for same-sex peers.
Cross section of heart with pacemaker leads
Night Attack on the Sanjo Palace (detail), from the Scrolls of Events of the Heiji Period.
Anthroposphere Quarterly Period
Embryonic Period
Embryonic Period
This table shows the growth of a crowd at a rally over a 3 h period.