How come a penis is at it's largest when erect?

Answer:
This is because there are lengths of tissue in the penis that are designed specifically to fill (engorge is the proper term) with blood when aroused. This means that the cells are fairly empty when limp (flaccid) and as a result smaller. Nipples also react the same way as does the female clitoris.

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Because there's increased blood flow to it.

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because thats when its time for you kow what! lol!

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because all the blood goes there

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A penis it at it's largest when erect is because that's when it's most aroused with pleasure and sometimes with frustrated pleasure, when a penis gets aroused it fills with blood, that's how a boy/men hard.

I hope this answers your question... :)

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Well, it would suck if it shrank.

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You cant really be asking this... noones this stupid.

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