Answer to this is copper wire
I think its because vaccines are just to help your body learn how to fight off the virus, it’s not to actually give you the virus. Hope this helped!
<span>Epithelial tissue is densely packed cells that used most in the area where protection is needed. This cells mostly used in skin, some with more keratin which will increase their ability to protect. In bone, the main protective layer is calcium mineral which was deposited by osteocytes. Because this bone doesn't really need more epithelial cells. Bone tissue only needs a good vascularization and connective tissue to support it.
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