|
|
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Asthma cases in Americans are about 75% higher today than they were in 1980.
Vaccines cause herd immunity. If the majority of people in a community have been vaccinated against a disease, an unvaccinated person is less likely to get the disease since others are less likely to become sick from it and spread the disease.
More than 30% of American adults, and about 12% of children utilize health care approaches that were developed outside of conventional medicine.
Your skin wrinkles if you stay in the bathtub a long time because the outermost layer of skin (which consists of dead keratin) swells when it absorbs water. It is tightly attached to the skin below it, so it compensates for the increased area by wrinkling. This happens to the hands and feet because they have the thickest layer of dead keratin cells.