Fast Facts

Introducing a new series of posts! Once a week I'll be posting a random fact, which will (hopefully) be fast, fun and fascinating.

Here's one that I find mind boggling.
This a red blood cell (also known as an erythrocyte):

Yes, it's an actual photograph.

Oxygen Molecule 

There are 4 to 5 million of these in one microliter of blood. (For visualization, there are about 50 microliters in a drop of water).

Red blood cells are really important because they carry oxygen throughout the body. About 1 billion molecules of oxygen bind to one red blood cell.

This means that there are ~ 4.5*10^15 or 4,500,000,000,000,000 oxygen molecules per microliter of blood.  Unbelievable, right?

God is amazing!