I am not sure what you mean but the testes work better at producing sperm when they are slightly cooler than the rest of the body. That is why the testes are in a sack of loose skin (the scrotum)...
Gravity.
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I am very curious as to what type of person would ask that...
It is not like you were raised by wolves, and grew up in a bush.. you are using a computer to ask the question, you...