Thecentral nervous system(CNS) is comprised of the brain and spinal cord.
The CNS receives sensory information from the nervous system and controls the body’s responses.
This article discusses the structures that make up the central nervous system and how they function.
The central nervous system is composed of the brain, spinal cord, and neurons.Sciepro/Science Photo Library/Getty Images
It also explores some of the diseases and conditions that can affect the CNS.
The surface of the brain is known as the cerebral cortex.
The surface of the cortex appears bumpy thanks to the grooves and folds of the tissue.
Each groove is known as a sulcus, while each bump is known as a gyrus.
The largest part of the brain is the cerebrum.
It is responsible for functions such as memory, speech, voluntary behaviors, and thought.
The cerebrum is divided into two hemispheres, the right hemisphere and the left hemisphere.
The spinal cord carries information from various parts of the body to and from the brain.
While it varies from one individual to the next, the spinal cord is about 18 inches in length.
Examples include the Golgi tendon reflex, the crossed extensor reflex, and the stretch reflex.
Neurons
Neurons are the building blocks of the central nervous system.
Neurons are the body’s information superhighway.
An estimated86 billion neurons can be found in the brain alone.
Most neurons are divided into three basic sections: dendrites, cell body, and axon.
These cells also differ in terms of function.
The three types of neurons are afferent neurons, efferent neurons, and interneurons.
Efferent neurons are motor neurons that carry signals from the brain to the peripheral nervous system.
Afferent neurons are sensory neurons that bring information from the senses to the brain.
Interneurons are association neurons that connect efferent and afferent neurons to the central nervous system.
Neurons are the cells that make up the central nervous system.
They are responsible for communicating information throughout the body.
Protective Structures
Since the CNS is so important, it is protected by a number of structures.
First, the entire CNS is enclosed in bone.
The brain is protected by the skull.
The spinal cord is encased by the vertebrae that make up the spinal column.
The brain and spinal cord are both covered with a protective tissue known as meninges.
The CNS is protected by structures including the skull, spinal vertebrae, meninges, and cerebrospinal fluid.
Damage or disease to the central nervous system can produce a range of effects.
Such diseases and damage can lead to impairment and sometimes death.
The gray matter is primarily made of neurons, while the white matter contains cell axons.
Both the white and gray matter contain glial cells that support and protect the neurons of the brain.
The structures that make up the CNS are delicate and susceptible to damage, injury, and disease.
Because these structures are so complex, the damage is usually permanent.
Paralysis is resulting from problems with the nervous system.
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