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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To prevent foreign investment in African economies
Answer: Those parts is were all the oxygen is distributed through the human body, and so technically it can be considered the respiratory system.
Answer:
TRUE
Explanation:
Yes, laughing gas can kill if used for recreational purposes without properly safety in place. All of the things listed in question can happen along with hypoxia (low O2 levels) if person does not breathe in O2 in regular intervals.
Setting limits helps you make responsible decisions because when you set limits you know how far you should or shouldn’t go.
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