The circulatory system is critical to human survival. It’s responsible for bring blood to every region of your body and it also maintains the balance of health. It fights disease, helps to heal injuries, and transports hormones and nutrients to the various cells throughout the body. Here are some other interesting facts about this system too.
1. It’s Super Long
If you stretched out the human circulatory system from end to end, you’d end up with more than 60,000 miles worth of tissues. That’s enough to orbit the world nearly 3 times. What makes this fact more impressive is that nearly 80% of that length is in the form of capillaries.
2. Cells Change
Red blood cells are unique because they can shift their shape. This has to be done because the capillaries are very small. Some are small enough that they force the red blood cells to travel in a single file line. Others are even smaller, which forces the red blood cells to change their shape in order to move through the body.
3. How Special Are They?
Red blood cells do more than just change their shape. They also have no nuclei, which means they are able to carry more oxygen to the rest of the body. Without a nucleus, the red blood cells will also end up dying from old age or from damage. That’s why bone marrow is so critical. That’s where no red blood cells are formed.
4. Size Matters
The heart can actually work less in larger beings. Babies tend to have the highest heart rates, often well above 100 beats per minute. For the average adult, a pulse rate of 75 is a pretty good number to have. If you’re bigger than average, however, your heart rate is going to be lower.
5. The Heart Moves On
Even when the heart is removed from the body, it will continue beating. This is because the muscle has an electrical impulse that is self-generated. This impulse is what causes the heart to beat. Even if it is all by itself, the heart will continued to beat as long as it receives oxygen in some way.
6. We Were Wrong
For nearly 1,500 years, humanity followed an incorrect version of the circulatory system. It was believed that humans had two different kinds of blood and that each had a different purpose. It was also thought that there were two circulatory systems instead of one integrated system.
7. Emotions Can Kill You
An extremely emotional event can actually cause your heart to actually break. It’s even called “Broken Heart Syndrome.” It causes symptoms that are similar to a heart attack and includes shortness of breath and the classic arm aching.
8. Blood Does Come in Different Colors
Some of the ancient theories about the circulatory system are true, namely the different colors of blood. Blood that has more oxygen tends to be brighter and blood without oxygen tends to be darker. Sometimes the blood looks a bit blue through the skin, but it usually just looks that way.