Infant Esme is just waking up from her nap. As her mom enters the room, Esme turns her head in Mom's direction. Which of the following allowed Esme to know the direction Mom would be entering from?

The most lethal disease for all children in past centuries was

polio. smallpox. rubeola. anencephaly.

The 48% concordance rate of schizophrenia in identical (monozygotic) twins, who share 100% of their genetic information, tell us that

a. schizophrenia is not a purely genetic disorder b. schizophrenia is not a purely environmentally-controlled disorder c. environmental influences play some role in schizophrenia d. genetic influences play some role in schizophrenia e. all of these