Brain in the skull__________23689

[Polshi]

The human brain operates using electrical signals between neurons. While the total power is only about 20 watts (roughly the power of a dim light bulb), it's enough energy to power some small electronic devices.

 

[Polshi]

The animal with three hearts is the Octopus. Two hearts pump blood to the gills, and one pumps blood to the rest of the body. Even stranger, their blood is blue because it uses copper-based hemocyanin instead of iron-based hemoglobin.