Here is a cool circulatory system video for anyone not to squemish to use.  I killed the turtle, let it hang for almost 3 hours and proceeded to butcher it.  What the video shows is the heart still beating in rhythm after the carapace has been opened, hind limbs removed and pericardium comprimised.  This is an excellent video that shows 1.  You dont need a brain more specifically the medulla to beat in rhythm and 2.  The incredible nervous system of the reptile.

[video:http://www.vimeo.com/1534934]