John says that he can't do many of the things required in his job. He feels very inferior to his supervisor and co-workers. "They really seem to understand how to do things. I wish I could be like that, but I can't"

Sleep disorders are often more common in childhood, most likely because children

a) sleep very deeply and spend more time in deep sleep b) are so easily awakened in the deep sleep stage c) spend less time in REM sleep than adults d) need less sleep than adults

Homozygous is to __________ as heterozygous is to __________

a. different; same b. similar; different c. fraternal; identical d. same; different e. one; two