The Human Body [best]

The "command center" of the human body is the , led by the brain. The brain contains approximately 86 billion neurons, forming a dense web of electrical signals that dictate our thoughts, memories, and involuntary actions.

Beyond the systems, the human body performs daily miracles we take for granted: The Human Body

Even when you are perfectly still, your body is a hive of activity: The "command center" of the human body is

Scientists typically divide the body into that carry out specific functions: Layer Systems The spinal cord acts as the

: Draw or print a basic human outline to use as a consistent base for every layer. Layer Systems

The spinal cord acts as the main data cable, transmitting instructions from the brain to the rest of the body. This system is so fast that we can react to pain or heat in a fraction of a second, often before our conscious mind even registers the sensation. The Chemistry Lab: Digestion and Metabolism