The autonomic nervous system has two divisions: The sympathetic division acts to energize the body, preparing it for action. The parasympathetic division acts to calm the body, allowing it to rest. Our everyday activities are controlled by the interaction between the sympathetic and parasympathetic nervous systems.
Update: N2Aos is now available for Kindle Fire HD and Kindle Fire HD 8.9. And you get the full Android experience here, including access to the Google Play store and all the other features offered by Android 4.2 (excepting what's not available via hardware, of course).
Learn how to download and install Show Box onto the Kindle Fire tablet or Fire Phone. Show Box is a free movie streaming app for Android devices. Since the Kindle Fire OS is Android based, Kindle users will be able to install Show Box onto it.