The fact that the rate of homosexual concordance is substantially higher for identical twins than for nonidentical twins shows that
A. sexual orientation is determined solely by environmental factors.
B. there is no genetic contribution to determining sexual orientation.
C. there is a genetic contribution to determining sexual orientation.
D. sexual orientation is determined solely by cultural factors.
Answer: C
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Indicate whether the statement is true or false.
Generally, all sexual orientations except heterosexuality are regarded as ________, which means they are not consistent with a society's dominant sexual and gender roles, norms, and relationships.
A. nonconforming sexual behaviors B. questioning sexual behaviors C. transgender behaviors D. homosexual E. bisexual
Which of the following is true of ejaculation?
A. The ejaculatory duct opens into the seminiferous tubules. B. Cowper's glands secrete fluid only after ejaculation. C. Upon ejaculation, sperms pass from one testis to the other. D. An average ejaculate contains about 200 million sperms.
Research shows that men who have had their spinal cords completely severed, as a result of accidents, at a level above that of the reflex center
A. are never able to ejaculate again. B. are able to experience orgasms as they normally would. C. cannot respond to the tactile stimulation of the genitals. D. are still capable of having erections.