Herd immunity involves a) encouraging individuals to work and live in close proximity to each other to prevent spread of a disease outside of a population b) maintaining a 100% vaccination rate among farm workers to prevent the spread of zoonotic diseases c) keeping bovine diseases to a minimum so they do not spread to the human population d) maintaining a certain level of immunized individuals in a society to prevent a pathogen from circulating through the population

Spherocytosis is an inherited blood disease in which the erythrocytes (red blood cells) are spherical instead of biconcave. this condition is inherited in a dominant fashion, with sph- dominant to sph+. in people with spherocytosis, the spleen "reads" the spherical red blood cells as defective, and it removes them from the bloodstream, leading to anemia. the spleen in different people removes the spherical erythrocytes with different efficiencies. some people with spherical erythrocytes suffer severe anemia and some mild anemia, yet others have spleens that function so poorly there are no symptoms of anemia at all. when 2400 people with the genotype sph- sph+ were examined, it was found that 2250 had anemia of varying severity, but 150 had no symptoms. does this description of people with spherocytosis represent incomplete penetrance, variable expressivity, or both? explain your answer. (3 points)

How is health different for most people in this country today from what it was for people born in 1900? a. people have a shorter life span. b. people today work harder to survive. c. people today live in poorer sanitary conditions. d. people today can focus less on day-to-day survival and more quality of life.

Anutritional study should take all of the following into account except taste in music. family medical history. work and home responsibilities. lifestyle factors, such as smoking or alcohol consumption.