How will you differentiate the central nervous system and the peripheral nervous system in terms of their functions?

Although terminology seems to indicate otherwise, there is really only one nervous system in the body. Although each subdivision of the system is also called a "nervous system," all of these smaller systems belong to the single, highly integrated nervous system. Each subdivision has structural and functional characteristics that distinguish it from the others. The nervous system as a whole is divided into two subdivisions: the central nervous system (CNS) and the peripheral nervous system (PNS).

The Central Nervous System

The brain and spinal cord are the organs of the central nervous system. Because they are so vitally important, the brain and spinal cord, located in the dorsal body cavity, are encased in bone for protection. The brain is in the cranial vault, and the spinal cord is in the vertebral canal of the vertebral column. Although considered to be two separate organs, the brain and spinal cord are continuous at the foramen magnum.

The Peripheral Nervous System

The organs of the peripheral nervous system are the nerves and ganglia. Nerves are bundles of nerve fibers, much like muscles are bundles of muscle fibers. Cranial nerves and spinal nerves extend from the CNS to peripheral organs such as muscles and glands. Ganglia are collections, or small knots, of nerve cell bodies outside the CNS.

The peripheral nervous system is further subdivided into an afferent (sensory) division and an efferent (motor) division. The afferent or sensory division transmits impulses from peripheral organs to the CNS. The efferent or motor division transmits impulses from the CNS out to the peripheral organs to cause an effect or action.

Finally, the efferent or motor division is again subdivided into the somatic nervous system and the autonomic nervous system. The somatic nervous system, also called the somatomotor or somatic efferent nervous system, supplies motor impulses to the skeletal muscles. Because these nerves permit conscious control of the skeletal muscles, it is sometimes called the voluntary nervous system. The autonomic nervous system, also called the visceral efferent nervous system, supplies motor impulses to cardiac muscle, to smooth muscle, and to glandular epithelium. It is further subdivided into sympathetic and parasympathetic divisions. Because the autonomic nervous system regulates involuntary or automatic functions, it is called the involuntary nervous system.

The human nervous system is a complicated system of connecting neurons and associated cells. The nervous system allows us to think, breathe and feel. Scientists categorize the nervous system into two main parts: the central nervous system (CNS) and the peripheral nervous system (PNS). These parts of the nervous system differ in their structures and physiological functions.

Basic Structures

The CNS consists of the brain and spinal cord, while the PNS includes all other nervous system tissue. All sensory receptors, sensory neurons and motor neurons are part of the PNS. The bones of the skull and spinal vertebrae encase all CNS neurons. Neurons in the PNS are not encased in bone; rather, they travel through or lie on top of muscle, organ and skin tissue. Groups of neurons form in both the CNS and the PNS. In the CNS, a group of neurons is called a nucleus. In the PNS, a group of cell bodies is known as a ganglion, while a bundle of neuron tracts is called a nerve.

Function

The primary purpose of the CNS is to organize and analyze information. Nervous system impulses run to and from the brain via the spinal cord. Different areas of the brain process sensory and motor information, allowing us to observe and react to our environment. The central purpose of the PNS is to follow the commands of the CNS. Neurons in the PNS gather sensory information from the environment and relay it to the CNS. After the CNS processes the information, the PNS responds to its commands by changing motor output.

Divisions

The brain and spinal cord are broken down by their general purposes. For example, the brain consists of the cerebrum, diencephalon, midbrain and hindbrain. Each brain region performs a specific set of tasks. The PNS is divided into the somatic nervous system and the autonomic nervous system. The somatic nervous system consists of consciously controlled nerves that receive sensory information and execute motor commands. The autonomic nervous system operates without conscious commands from the brain. It monitors heart rate, digestive activity, breathing, salivation and sexual arousal.

Considerations

Experts divide the nervous system into the CNS and PNS to classify its important functions. However, both parts of the nervous system work in tandem and are essential to life. Without the PNS, the CNS would not have any sensory input to process, making it impossible to react to the environment. Likewise, the PNS relies upon the CNS to coordinate information from different body parts and make decisions about how you should react in a given situation. These two parts of the nervous system work together in synchrony to create our conscious experience of everyday life.

How will you differentiate the central nervous system and the peripheral in terms of their function?

What is the difference between central nervous system and peripheral nervous system?

What is the main difference between the central nervous system CNS and the peripheral nervous system PNS )? Quizlet?