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[ Level 4 ]
 "Whew, I feel a little better. The probe has entered my heart but the pain has subsided. The Humanoids have taken a break from injecting me. I've got to find a way out of here.

I can't even describe what has happened. My hands...they've grown claws and my arms are twice their normal size. I actually feel like I could lift a car. Maybe with this new strength I can escape. Wait, I think they're coming back!" (Dr. Bruce Grey)


QUESTION:
After deoxygenated blood enters the atria, the atria contract and force blood into the ventricles through the ______________ valves.