Trisomy 13, trisomy 18, and trisomy 21 are all causes of mental retardation associated with
a) prenatal infections.
b) metabolic dysfunctions.
c) fragile areas on the X chromosome.
d) more than the normal number of chromosomes.
d
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Grandma Burns lived to the age of 102. To better understand how she lived a long life, you ask your family physician. Your physician is least likely to cite which factor of her life trajectory as a key to her longevity??
a. ?having positive self-perceptions in middle adulthood b. ?being introverted as a child c. ?being a woman d. ?having a group of genes that inhibit aging
Which of the following is NOT true of sex in homosexual relationships?
a. Gay males engage in sex more frequently than other types of couples. b. Lesbian couples have sex less often than other couples. c. For both gays and lesbians, sexual satisfaction is correlated with overall relationship satisfaction. d. Declines over time of sexual behavior noticed in heterosexuals do not apply to homosexuals.