Communication systems
The human body has two communication systems that allow us to respond to any changes in our environment.
The nervous system uses nerve impulses (electrical impulses) to react quickly to a Something that sets off a reaction in the nervous system, for example, light, heat, sound, gravity, smell, taste, or temperature. These changes in the environment are detected by receptors in an organism. The plural is stimuli..
The hormonal system uses Chemical messengers produced in glands and carried by the blood to specific organs in the body. to react slowly to a stimulus.
| Nervous system | Hormonal system | |
| Speed | Fast | Slow |
| Nature of response | Electrical impulses | Hormones/chemicals that travel in blood |
| Speed | |
| Nervous system | Fast |
| Hormonal system | Slow |
| Nature of response | |
| Nervous system | Electrical impulses |
| Hormonal system | Hormones/chemicals that travel in blood |
The nervous system
The brain and The part of central nervous system of a mammal which runs inside its backbone form the central nervous system (CNS). The CNS controls and coordinates responses between Organ, tissue or cell that detects a stimulus. and The organ, tissue or cell that produces a response..
- Stimuli are changes in our environment that we respond to and are detected by receptors.
- Different receptors are sensitive to different stimuli (e.g. receptors in the eye are sensitive to light).
- A nerve cell/neurone carries information in the form of nerve impulses from the receptor to the The central nervous system, it determines the correct response to a stimulus..
- The coordinator – brain or spinal cord – determines whether or not to respond to the stimulus.
- A neurone carries information from the coordinator to an effector.
- An effector is a muscle or gland that can bring about a response.
