Give one example of a way that heredity influences body size. Give another example of how lifestyle influences body size.

[120 total points] (public health) in one of the largest human experiments ever conducted, in 1954 a randomized controlled trial was run to see whether a vaccine developed by a doctor named jonas salk was effective in preventing paralytic polio. a total of 401,974 children (ages 6–9), chosen to be representative of those who might be susceptible to the disease, were randomized to two groups: 200,745 children (the control group c) were injected with a harmless saline solution (a placebo) and the other 201,229 children (the treatment group t) were injected with salk’s vaccine. what was the point of giving saline solution to the children who didn’t get the vaccine? explain briefly.

For years, tobacco products have included a message from the surgeon general warning the negative effects of tobacco use. at this time, a push is being made for the fda to begin to regulate e-cigarettes in order to mandate warning labels and age restrictions. write a paragraph that identifies 2 health problems that have been linked to nicotine and/or tobacco use. you should include statistics demonstrating the incidence of problems among smokers and provide a resource citing where you found the information provided. (remember from unit 1 what makes a resource reliable.) due in 2

Why do you need two different circuits of blood vessels in your body?