Neuroglial cells provide physical support and protection to neurons. In the peripheral nervous system, neuroglial cells called Schwann cells produce a lipoprotein called myelin which insulates the neuron, speeds up the transmission of impulses, and assists in axonal regeneration in the event of an injury. Neuroglial cells of the central nervous system are called oligodendrocytes. Oligodendrocytes also provide myelin, to insulate neurons and speed up transmission of impulses, but oligodendrocytes do not assist in regeneration.
The central nervous system (CNS) comprises grey matter, which contains neuron cell bodies and white matter, which contains the nerve axons. Most of the nerve axons are concentrically wrapped around by lipid-rich biological membrane, known as the myelin sheath. In the CNS, myelin is produced by oligodendrocyte. a type of glial cell. (Pfeiffer et al., 1993). These electrical insulating, multilamellar membranes significantly increase the electrical resistance, in which to prevent leakage of electrical currents from the axons, as well as decrease electrical capacitance to reduce the ability of the axons to store electrical energy (Shivane &
The CNS contains the brain and spinal cord. Its main functions include: processing, integrating, and coordinating sensory information and motor instructions. The sensory data conducts information that is being processed from internal and external conditions the body is experiencing. Motor commands regulate and control peripheral organs (skeletal muscles). The brain functions under memory, emotions, learning, and intelligence. The PNS consist of the neural tissue found outside of the CNS. It functions in sending data to the CNS which motor commands are than carried out to the peripheral tissues/systems. Multiple nerve fibers send sensory data and motor commands in the PNS. The nerves that assist with transmitting data include the cranial nerves and spinal nerve. However, the PNS can be divided into afferent (to bring in) and efferent (to bring out) divisions of transferring data. The afferent division functions in bringing in sensory data to the CNS. Sensory structures are receptors that detect internal/external environmental change and adjusting accordingly. The efferent division functions in carrying out motor commands from the CNS to glands, muscles, and adipose tissue. The efferent division contains somatic
Nerve cells generate electrical signals to transmit information. Neurons are not necessarily intrinsically great electrical conductors, however, they have evolved specialized mechanisms for propagating signals based on the flow of ions across their membranes.
The CNS is further supported by a series of blood vessels that travel through and around the brain bringing oxygen and nutrients that are required for cell health. The CNS is further segmented by lobes such as the frontal lobe which the main role is executive function, long term memory and primary motor function. The temporal lobe which is responsible for language and sensory functioning, and the parietal lobe are responsible for somatosensory functions, and occipital lobe which is the visual association area (Hendelman, 2006). Each of these lobes controls cognitive functions, memory, motor, sight, smell, emotions and bodily functions, and are interconnected by the corpus callosum. Further structures include the basal ganglia, the brainstem, the cerebellum, the diencephalon, the thalamus and the hypothalamus, which are all divided and supported via the ventricles and sulcus which is where the cerebral spinal fluid [CSF] fills and acts as a cushion and nutrient for the brain (Hendelman, 2006). In a healthy functioning person all of these complex structures interconnect to control and regulate not only bodily functions, temperatures, nutrients, and processes, but also complex cognitive and psychological processes. A healthy brain additionally has smaller amounts of accumulated beta-amyloid plaques which can form extracellular aggregations of fibrils, as well as less of hyper-phosphorylation of tau protein which helps to create intracellular neurofibrillary tangles. A healthy brain additionally has balanced neurotransmitters and blood devoid of cholesterol and with balanced blood sugars (Bryant & Knights ,
The CNS is made up of the brain and spinal cord, while the PNS is made up of the rest of the body. The CNS receives sensory information and the PNS relays motor information from the CNS to the muscles and organs of the body. The CNS is encased with bones while the PNS is not usually encased with bones and it touches other parts of the body. Axons in the PNS are myelinated by Schwann cells while cells in the CNS are myelinated by oligodendrocytes.
To send a message, a neuron will send a ripple of electrical energy down its axon. This ripple is called "action potential." The way it works is by changing the chemical makeup of the axon's negatively charged interior. Positively charged sodium ions move into the cell and negatively charged potassium ions move out, then the ions move to their original positions. This produces a wave of positively charged
The astrocytes are shaped like a star and it is also known as a star cell. Astrocytes supports the neurons and cleans the brain and control chemicals that are around the neurons. When the cells die from the central nervous system the astrocytes cleans the debris away. When a small portion of the debris that is apart of a neuron die; the astrocytes will move them, this process is called phagocytosis. The Oligodendrocytes mainly supports axons and creates a myelin sheath. The shape of the oligodendrocytes is made in the CNS; The oligodendrocytes is shaped like a paddle. While the oligodendrocytes is the paddle form, the oligodendrocytes shapes the myelin with a axon that are made in the CNS. The Schwann cells is the supporting cells in the PNS but the schwann cells do same thing as the oligodendrocytes. Microglia is the smallest cells of the three types of glias. These small cells are apart of the immune system of the brain. The microglia takes care of the brain from the other organisms. Radial glia is a glia that has fibers that guides the neurons to migrate while the brain is
Answer 1: Glial cells are cells that surround neurons and provide support for and insulation between them. Glial cells are also the most abundant cells in the central nervous system. Types of glial cells include oligodendrocytes, which have processes that form the myelin sheaths around CNS nerve fibers, astrocytes the most abundant CNS neuroglia, ependymal cells that line cerebrospinal fluid cavities, microglia cells that are the defensive cells in the CNS, schwann cells and satellite cells, which form myelin sheaths around CNS never fibers.
Glial cells make up 90 percent of the brain's cells. Glial cells are nerve cells that don't carry nerve impulses. The various glial (meaning "glue") cells perform many important functions, including: digestion of parts of dead neurons, manufacturing myelin for neurons, providing physical and nutritional support for neurons, and more. Types of glial cells include Schwann's Cells, Satellite Cells, Microglia,
Neuronal messages are transmitted by electrical impulses called the Action Potential. This is actually a net positive inward ion flux that leads to depolarization or voltage change in the neuronal membrane. The ions involved include sodium, potassium, calcium and chloride. Normally brain tissues prevent hyper excitability by several inhibitory mechanisms involving negative ions like chloride ions.
Glial cells are the most numerous cells in the brain, outnumbering neurons nearly 3:1, although smaller and some lacking axonal and dendritic projections. Once thought to play a subpar role to neurons, glial cells are now recognized as responsible for much greater functions. There are many types of glial cells, including: oligodendrocytes, microglia, and astrocytes. Oligodendrocytes form the myelin sheath in the CNS, by wrapping themselves around the axons of neurons. Their PNS counterpart, Schwann cells, are also considered glial cells. This sheath insulates the axon and increases the speed of transmission, analogous to the coating on electrical wires. Microglia are considered to be “immune system-like”; removing viruses, fungi, and other wastes that are present. Astrocytes, however, are considered to be the most prominent. Their functions span throughout the brain, including, but not limited to: the synchronization of axonal transmission via G-protein-coupled receptors, blood flow regulation via the dilation of blood vessels, and the performance of reactive gliosis in conjunction with microglia. Both astrocytes and oligodendrocytes develop from neuroepithelial cells. Other types of glial cells include Radial glia, which direct immature neuron migration during development.
Inflammation is a reaction of tissues in response to any injury the human or vertebrae sustains. Neuroinflammation is the inflammatory response by the glial cells that are present in the nervous system along with neurons. It is an immune response to pathogen invasion or tissue damage most likely to be caused by Infectious bacteria, Traumatic brain injury (TBI), or toxic metabolites. The nervous system contains neurons and glial cells composed of astrocytes, microglia, oligodendrocytes, ependymal cells in the Central nervous system (CNS), and Schwann cells, satellite cells in Peripheral nervous system (PNS). The glial cells are non-neuronal cells that help to form myelin, maintain homeostasis, provide support for neurons with nutrients, destroy
The fluid in the brain (cerebrospinal fluid or CSF) is formed in the brain. CSF usually circulates through parts of the brain, its covering, and the spinal canal, and is then absorbed into the circulatory system.