Organs are run by the Limbic system. It's get's it's orders from the brain. No orders, no worky. No worky, no life. The brain is reasonbly protected by the skull. If there's a weak spot, it's the neck area. That's why the US Marines wore leather collars before WWII, to protect the neck area from saber blows. Hence the name "Leathernecks."
Gravity