During cell division in a zygote, one cell divides and forms a heart cell and another cell divides and forms a brain cell. Which of the following best describes the process that is taking place?

The National Research Council reported in 2013 that life expectancy in the U.S. lags behind other high-income countries for four reasons. Which of the following is one of those reasons?

a. poor health behavior like excessive smoking, drinking, and eating b. people below the poverty line demanding access to excessive amounts of healthcare c. web-based medical information programs and social support networks providing misinformation d. high percentage of exercise-related injuries leading to premature death

Alison Clarke-Stewart, an expert on day care, has summarized the literature to provide a series of guidelines for quality day care. Which of the following is among her recommendations?

a. There should be at least one caregiver for every fifteen children. b. Children should have free choice of activities with no structured lessons. c. Caregivers should be responsive to the children's needs and actively involved in their activities. d. Caregivers should observe children's activities but should not become involved in them.