Because humans have five senses: feel, see, taste, hear, and smell. When you step on a nail you basically going to feel it and you brain can sense that and it can trigger nerves which can cause pain.
When the skin is exposed to ultraviolet rays, the skin produces a molecule that is turned into Vitamin D.
Sun is the source of ultraviolet rays important for Vitamin D production. Due to this reason, in the case of Vitamin D deficiency, it is recommended by doctor's to absorb sunlight by skin. The Vitamin D production occurs specifically by UV B rays rays which lie in the range of 290-315 nanometer.
The chemical 7-dehydrocholesterol absorbs these rays and convert to previtamin D3. Further, previtamin D3 isomerizes to Vitamin D. Other than sunlight, Vitamin D can be taken through diet. The sources include seafood like fish, fish oil, dairy products, beef liver etc. Vitamin D is required for bone and teeth formation, muscle contraction, immune system etc.
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You need to sometimes break ribs to pump blood in the heart by doing CPR (CC)
Drink water and go to sleep. There is no easy way to sober someone up
Your maximum heart rate (MHR) id dependent on several factors and an
individual should take care when assessing this. There are a few
formulas commonly used in sports science circles and the most common of
these is equation is 220 – age = maximum heart rate (MHR) so answer C
fits as the correct solution.
