Amazing Facts Of Blood

Everybody knows that when you get cut, you bleed which is a result of the perpetual movement of blood through our bodies. But do you even know about all the functions of the circulatory system that what they actually perform? Here are some surprising facts about human blood.
1. Doctors still use bloodletting and sycophant to treat diseases.
Ancient peoples knew the circling system was important to overall health. And it may be one of the reason for bloodletting, it is the practice of cutting people to serve them a “cure” everything from cancer to infections to mental illness. For the better part of two millennia, it holds on as one of the most common medical procedures.
2. Scientists did not understand how blood circulation worked.
In part by sterilize living animals and studying about their still-beating hearts, Harvey was able to explain in details that how the heart works and pumped blood into the body and how blood returned to the heart. He also showed how hydrant in veins helped control the flow of blood through the body.
3. In the early 20th century types of blood were discovered
In 1901, Austrian physician Karl Landsteiner discovered different blood groups, after he noticed that blood mixed from people with different types would clot. His successive research classified types A, B and O. (Later research identified an additional type, AB). Blood types are differentiated by the kinds of antigens—molecules that enrage an immune system reaction—which is attach to red blood cells.
4. The sight of blood can make people faint.
For 3 to 4 percent of people, biliousness correlate with blood, injury, or meddling medical procedures like injections rises to the level of a true phobia called blood injury injection phobia (BII). And most sufferers share a common reaction: fainting.
Most phobias cause an increase in heart rate and blood pressure, and often muscle tension, shakes, and sweating: part of the body’s supportive nervous system’s “fight or flight” response.

By: Tripti Varun
Content: http://mentalfloss.com/article/87499/7-sanguine-facts-about-human-blood