Involuntary Muscular Contractions

[Burgs]

A Professor was giving a lecture on "Involuntary Muscular Contractions" to his first year medical student.
Realizing that this was not the most riveting subject, the Professor decided to lighten the mood slightly.

He pointed to a young woman in the front row and said, "Do you know what your ass hole is doing while you're having an orgasm?"

She replied, "Probably roo shooting with his mates."

The professor laughed so hard he could not continue with the class

[frontrow]

I laughed so hard i nearly fell off my chair...