The Organs of the nervous system
Neurons and Neuroglia
Neurons, also called nerve cells, communicate within the body by transmitting electrochemical signals. Neurons look very different from other cells in the body. Neurons typically have a nucleus, mitochondria and other cell organelles. Small structures called dendrites extend from the cell to pick up stimuli from the environment and other neurons. There are main 3 kinds of neurons. They are Afferent neurons, Efferent Neurons and Interneurons. Afferent Neurons, also known as sensory neurons, send signals which are received from your senses, to the central nervous system. Efferent neurons, which can also be called motor neurons, send signals from the central nervous system to the effectors in your body, such as the muscles and glands. Finally, Interneurons form complex networks within the central nervous system to interpret the information recieved from the afferent neurons and direct the functions of the body through efferent neurons. Neuroglia, also known as glial cells, act as secondary “helpers” in the nervous system. Each neuron in the body is surrounded by 6 to 60 neuroglia cells that protect, feed and insulate the neuron. Because neuroglia cells are important to the body and almost never reproduce, they are vital in order to keep a healthy body.
Neurons, also called nerve cells, communicate within the body by transmitting electrochemical signals. Neurons look very different from other cells in the body. Neurons typically have a nucleus, mitochondria and other cell organelles. Small structures called dendrites extend from the cell to pick up stimuli from the environment and other neurons. There are main 3 kinds of neurons. They are Afferent neurons, Efferent Neurons and Interneurons. Afferent Neurons, also known as sensory neurons, send signals which are received from your senses, to the central nervous system. Efferent neurons, which can also be called motor neurons, send signals from the central nervous system to the effectors in your body, such as the muscles and glands. Finally, Interneurons form complex networks within the central nervous system to interpret the information recieved from the afferent neurons and direct the functions of the body through efferent neurons. Neuroglia, also known as glial cells, act as secondary “helpers” in the nervous system. Each neuron in the body is surrounded by 6 to 60 neuroglia cells that protect, feed and insulate the neuron. Because neuroglia cells are important to the body and almost never reproduce, they are vital in order to keep a healthy body.
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The Brain
The brain plays a major role in the nervous system. It is the main control center of the body. The brain, which is about three pounds, is located in the cranial cavity. The bones of the skull surround and protect it. It is formed by nearly 100 billion neurons. The brain and spinal cord form the central nervous system(CNS), where information is processed and responses are made. The brain controls every function in the body, from memorizing things to the heart rate. The brain has three main parts. One is the cerebrum, which helps to control your senses such as vision and touch. Thinking also takes place in the cerebrum. The Cerebrum makes up most of the brain. Another part of the brain is the cerebellum, which helps control balance and physical coordination. The last major part of the brain is the brain stem. The brain stem is linked to the spinal cord and controls breathing, digestion, heart rate and more.
The brain plays a major role in the nervous system. It is the main control center of the body. The brain, which is about three pounds, is located in the cranial cavity. The bones of the skull surround and protect it. It is formed by nearly 100 billion neurons. The brain and spinal cord form the central nervous system(CNS), where information is processed and responses are made. The brain controls every function in the body, from memorizing things to the heart rate. The brain has three main parts. One is the cerebrum, which helps to control your senses such as vision and touch. Thinking also takes place in the cerebrum. The Cerebrum makes up most of the brain. Another part of the brain is the cerebellum, which helps control balance and physical coordination. The last major part of the brain is the brain stem. The brain stem is linked to the spinal cord and controls breathing, digestion, heart rate and more.
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The Spinal Cord
The spinal cord is a long thin mass of bundled neurons. It carries information through the vertebral cavity of the spine. The Spinal Cord begins at the Medulla Oblongta of the brain and continues to the lumbar region of the spine. In the lumbar region, the spinal cord separates into individual nerves called Cauda Equina and continues to the coccyx and sacrum. The white matter of the spinal cord acts as the main conduit of nerve signals to the body from the brain. The grey matter of the spinal cord controls it's reflexes to stimuli. Some of the messages are processed by Spinal Cord but most of them are passed on to the brain. The spinal cord is about 43 cm in women and about 45 cm in men. There are 31 pairs of spinal nerves.
The spinal cord is a long thin mass of bundled neurons. It carries information through the vertebral cavity of the spine. The Spinal Cord begins at the Medulla Oblongta of the brain and continues to the lumbar region of the spine. In the lumbar region, the spinal cord separates into individual nerves called Cauda Equina and continues to the coccyx and sacrum. The white matter of the spinal cord acts as the main conduit of nerve signals to the body from the brain. The grey matter of the spinal cord controls it's reflexes to stimuli. Some of the messages are processed by Spinal Cord but most of them are passed on to the brain. The spinal cord is about 43 cm in women and about 45 cm in men. There are 31 pairs of spinal nerves.
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Nerves
Nerves are a bunch of axons in the Peripheral Nervous System(PNS) that act as informational highways to carry signals throughout the body. Each axon is wrapped in a tissue that connects with other tissues called Endoneurium. Individual axons are grouped into Fascicles, wrapped in tissue called Perineurium. Finally, Fascicles are wrapped by another connective tissue called Epineurium to form a whole nerve. By wrapping nerves with all these connective tissues, the axons are protected and the communication within the body tends to speed up. Some different kinds of nerves include Afferent, Efferent, Inter Neurons, Cranial and Spinal Nerves.
Divisions of the nervous system
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Central Nervous System
The brain and spinal cord form the Central Nervous System, or CNS. The Central Nervous System is the main control center of the body. It provides processing, memory and regulation systems. The Central Nervous System is always aware of what is happening within it and around and outside it. It survives by maintain the body's homeostasis, and it's own decisions's help it ensure that. Also, the CNS is also responsible for your mental perceptions, especially the unnoticeable one's like emotions, personality, creativity, expression and feelings. The brain is the "boss" of the nervous system and control's most of the important things in your body.
Peripheral Nervous System
The peripheral nervous system is consists of nerves and ganglia, and is outside the brain and the spinal cord. The Peripheral Nervous System extends to other parts of your body, like the arms and the legs. The main function of the Peripheral Nervous System is to connect the CNS to parts of your body other than the brain and the spinal cord. It does not have the protection of the bones from from the spinal cord, as the CNS does. It is therefore left exposed to toxins and physical injuries. The nervous system is divided into two main parts, the Somatic System and the Autonomic nervous system. The Somatic system consists of motor nerves fibers that come out of the brain. They pick up mostly sensory signals from other organs, especially those that are a far distance away. They usually travel through the skeletal system. An example of when the somatic system takes action is when is when one of your fingers touch a hot object and the signal gets sent to the brain directly to move your finger. This whole process is very quick, often less than a second. The Autonomic system controls functions mainly related to your health and wellness. Some examples of it are heartbeat, digestion, unconscious breathing and general wellness. The autonomic nervous system is divided into 3 parts, the Sympathetic system, the Parasympathetic system and and the Enteric nervous system.
The brain and spinal cord form the Central Nervous System, or CNS. The Central Nervous System is the main control center of the body. It provides processing, memory and regulation systems. The Central Nervous System is always aware of what is happening within it and around and outside it. It survives by maintain the body's homeostasis, and it's own decisions's help it ensure that. Also, the CNS is also responsible for your mental perceptions, especially the unnoticeable one's like emotions, personality, creativity, expression and feelings. The brain is the "boss" of the nervous system and control's most of the important things in your body.
Peripheral Nervous System
The peripheral nervous system is consists of nerves and ganglia, and is outside the brain and the spinal cord. The Peripheral Nervous System extends to other parts of your body, like the arms and the legs. The main function of the Peripheral Nervous System is to connect the CNS to parts of your body other than the brain and the spinal cord. It does not have the protection of the bones from from the spinal cord, as the CNS does. It is therefore left exposed to toxins and physical injuries. The nervous system is divided into two main parts, the Somatic System and the Autonomic nervous system. The Somatic system consists of motor nerves fibers that come out of the brain. They pick up mostly sensory signals from other organs, especially those that are a far distance away. They usually travel through the skeletal system. An example of when the somatic system takes action is when is when one of your fingers touch a hot object and the signal gets sent to the brain directly to move your finger. This whole process is very quick, often less than a second. The Autonomic system controls functions mainly related to your health and wellness. Some examples of it are heartbeat, digestion, unconscious breathing and general wellness. The autonomic nervous system is divided into 3 parts, the Sympathetic system, the Parasympathetic system and and the Enteric nervous system.
Functions
Sensory
The sensory function of the nervous system involves collecting information from sensory receptors that monitor the body’s internal and external conditions. These signals are then passed on to the central nervous system (CNS) for further processing by Afferent neurons (and nerves). The Somatic System plays a major role when it comes to the function of sensory. The neurons don't assist in the sensory sense as they are used more for physical things. The CNS and PNS both play major roles.
Integration
The act of integration when you process many sensory signals that are passed into the CNS at any time. These signals are evaluated, compared and used used for decision making, discarded or committed to memory as deemed appropriate. Integration takes place in the gray matter of the brain and spinal cord and is performed by interneurons. Many interneurons work together to form complex networks that provide this processing power. This process is done fairly quickly, but not as fast as the sensory organs. You may notice sometimes that it takes long to make a decision and it depends entirely on what the decision is.
Motor
Once the networks of interneurons in the CNS evaluate sensory information and decide on an action, they stimulate efferent neurons. Efferent neurons (also called motor neurons) carry signals from the gray matter of the CNS through the nerves of the peripheral nervous system to effector cells. The effector may be smooth, cardiac, or skeletal muscle tissue or glandular tissue. The effect then releases a hormone or moves a part of the body to respond to the stimulus. Gross motor skills and fine motor skills are both effected by this sensory component.
The sensory function of the nervous system involves collecting information from sensory receptors that monitor the body’s internal and external conditions. These signals are then passed on to the central nervous system (CNS) for further processing by Afferent neurons (and nerves). The Somatic System plays a major role when it comes to the function of sensory. The neurons don't assist in the sensory sense as they are used more for physical things. The CNS and PNS both play major roles.
Integration
The act of integration when you process many sensory signals that are passed into the CNS at any time. These signals are evaluated, compared and used used for decision making, discarded or committed to memory as deemed appropriate. Integration takes place in the gray matter of the brain and spinal cord and is performed by interneurons. Many interneurons work together to form complex networks that provide this processing power. This process is done fairly quickly, but not as fast as the sensory organs. You may notice sometimes that it takes long to make a decision and it depends entirely on what the decision is.
Motor
Once the networks of interneurons in the CNS evaluate sensory information and decide on an action, they stimulate efferent neurons. Efferent neurons (also called motor neurons) carry signals from the gray matter of the CNS through the nerves of the peripheral nervous system to effector cells. The effector may be smooth, cardiac, or skeletal muscle tissue or glandular tissue. The effect then releases a hormone or moves a part of the body to respond to the stimulus. Gross motor skills and fine motor skills are both effected by this sensory component.