|
|
Pope Sylvester II tried to introduce Arabic numbers into Europe between the years 999 and 1003, but their use did not catch on for a few more centuries, and Roman numerals continued to be the primary number system.
Human kidneys will clean about 1 million gallons of blood in an average lifetime.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
According to the National Institute of Environmental Health Sciences, lung disease is the third leading killer in the United States, responsible for one in seven deaths. It is the leading cause of death among infants under the age of one year.
Children with strabismus (crossed eyes) can be treated. They are not able to outgrow this condition on their own, but with help, it can be more easily corrected at a younger age. It is important for infants to have eye examinations as early as possible in their development and then another at age 2 years.