|
|
When blood is deoxygenated and flowing back to the heart through the veins, it is dark reddish-blue in color. Blood in the arteries that is oxygenated and flowing out to the body is bright red. Whereas arterial blood comes out in spurts, venous blood flows.
In the United States, an estimated 50 million unnecessary antibiotics are prescribed for viral respiratory infections.
More than 4.4billion prescriptions were dispensed within the United States in 2016.
The first documented use of surgical anesthesia in the United States was in Connecticut in 1844.
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.