The human body hope this helps
You need to be more specific. There is more than one joint in a human hand.
1- Pain is useful becuase sometimes our body is trying to help but at the same time its causing you pain. Its adaptive because you can do things to avoid pain.
2- Without the proper signaling, neurons die by a process of self-destruction called apoptosis. Loss of sensory neurons leads to the inability to feel pain in people with CIPA. In addition, people with CIPA lose the nerves leading to their sweat glands , which causes the anhidrosis seen in affected individuals
3- Other negative states could include body healing, puperty, and even growing pains. But in the long run, pain can be very useful.
Explanation:
The blood brings oxygen to the body cells<span> and takes away their carbon dioxide. The blood that travels </span>back<span> to the </span>heart<span> and </span>lungs<span> is </span>dark red<span>. It has picked up carbon dioxide from the </span>body cells<span>, and it has left most of its oxygen with the cells.
</span><span>http://lsa.colorado.edu/essence/texts/lungs.html
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