| A | B |
|---|
| Coordinate | Work together |
| Hormone | A chemical signal that glands produce. |
| Impulse | A message that travels along nerve cells. |
| Neurotransmitter | A chemical signal that a nerve cell releases. |
| Nerve net | A bunch of nerve cells that are loosely connected. |
| Central nervous system | The brain and spinal cord. |
| Peripheral nervous system | The nerves that send messages between the centeral nervous system and other body parts. |
| Cerebrum | The largest part of the brain that controls thought, memory, learning, feeling, and body movement. |
