10 Fascinating Science Facts You Didn’t Even Know You Needed to Know
Discover something new with these ten snippets of intriguing science to spur curious minds.
Most of the cells in your body aren’t yours.
Strange but true. Despite everything we do in modern Western culture to avoid germs, we are nonetheless walking germ incubators, hosting bacterial infestations from the skin to the deepest parts of the gut. Studies suggest there are ten times as many microbe cells in your body as cells that have your own DNA (thankfully bacteria are small compared to human cells and so don’t take up as much space). Bad though that might sound, overall it’s actually a very good thing. For instance bacteria produce chemicals that help you harness energy and nutrients from your food. And around forty human genes appear to have come from bacteria. Having “good” bacteria on your skin can also stop more harmful varieties from getting a foothold. For children, early exposure to bacteria is a vital part of building a healthy immune system.
Why tiny “paper cuts” hurt so much.
It isn’t only paper cuts which seem to bring pain disproportionate to their size. Any shallow cut or other wound which is not sealed off, such as an ulcer or a burn, will probably hurt more than a deeper one. The main cause of the extra pain from shallow cuts is in fact a lack of blood. Because a shallow cut doesn’t bleed very much, the pain receptors are left open to the air, ensuring continued pain. Paper cuts also cause surprisingly acute pain since they usually involve a large number of skin surface pain receptors in a small area of the skin. The fibres from paper and chemicals present in it, such as bleach, can also cause extra irritation. Additionally, paper cuts normally occur in the fingers, which just happen to be where you have the greatest concentration of sensory receptors. A paper cut on your thigh for example wouldn’t hurt nearly as bad because the thigh doesn’t get nearly as much attention from your brain when it comes to feeling pain.
What makes the sky and sea blue?
A cloudless sky is blue because of the way the light from the sun is affected by the molecules which make up the air. As the sunlight enters the atmosphere, part of it is bent or scattered. However the air scatters blue light much more than other colours. Because that scattering happens in all directions, the light hitting your eyes is mostly the scattered blue light, which makes the sky appear blue overall. The same effect makes the sunset red and orange. When the sun is at the angle where sunsets are visible, the blue light is being scattered away from your line of sight, leaving the red and orange colours to predominate.