The human structure consists of many parts that make us human. Of course everyone knows we have a head, a neck, arms and legs. Lots of people live full and amazing lives without the use of their arms or legs—look at the famous physicist Stephen Hawking!—but living without smaller parts like the heart is impossible.
Did you know there are lots of tiny parts of the human body that are invisible to the naked eye yet play important roles in how our body functions? For many years, scientists have been trying to estimate how many cells our bodies have. Five billion? Two-hundred trillion?
It’s difficult to count because our cells come in many different sizes and grow in different densities. Red blood cells are very dense but skin cells are widely spread. Our bodies have about 50 billion fat cells but 2 billion heart muscle cells. How can scientists guess the number of cells in the human body if they can’t really count them? They perform some complicated math and do their best estimate: Our bodies consist of more than 37 trillion cells!
There are many other surprising facts about the human body. Did you know our bodies are 75 percent water? That your nose can detect 50,000 different scents? That there are 100,000 miles of blood vessels in the adult human? The human body is fascinating and mysterious. Learn more with these 25+ Amazing facts about the human body. Share them with your friends and family: