Neuroscience

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.

brain. The cells play a great part of our brain. I want to know more about the surrounding and

7. Myelin Sheath whitish fatty segmented sheath around most long axons. It protects the axon, electrically insulates fibers from one another , and increases the speed of nerve impulse transmition.

There are many symptoms associated with the physiological responses of the fight-or-flight including dilation of pupils, increased and more rapid heart rate, and acceleration in the respiratory system. The fight-or-flight response is a very important and crucial response both mentally and physically that is a building block for the human body. Without it, humans may not be as adapted to the dangerous and stressful environment we call our world. Finally, to summarize the steps of the fight-or-flight response. First, a threat or stimuli are perceived by the retina and signals are sent to the brain. Next, the brain processes the signals and determines whether the threat is real. Then, the adrenal medulla is sent synapses from the cerebrum and secretes a liquid with high levels of adrenaline called epinephrine. After that, the secreted adrenaline is mixed with glucose. Next, the adrenaline and glucose are rushed throughout the bloodstream and to the muscles. The muscles then tense up and are given an extra boost of strength and speed. Lastly, the muscles are used to either fight or

The term Glia is Greek in origin and means glue, this symbolic relationship between Glia’s name, and its function becomes ever more apparent when we learn that Glia cells secure the brain’s neurons together and protects them. Glial cells are crucial to the body’s ability to maintain homeostasis and contribute to almost all forms of homeostasis, such as regulating capillary flow, maintaining the blood brain barrier, extracellular respiration, and can even provide lactate to the neurons for energy. This essay will specifically be examining the Glia cells located within the Central Nervous System.

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.

Glial cells, also called neuroglia or simply glia, are non-neuronal cells that provide support and nutrition, maintain homeostasis, form myelin, and participate in signal transmission in the nervous system. In the human brain, glia are estimated to outnumber neurons by about 10 to 1 (SFN 2000).

The sympathetic nervous system activates what is often termed the fight or flight response. Like other parts of the nervous system, the sympathetic nervous system operates through a series of interconnected neurons.

The stress response involved the HPA-hypothalamic-pituitary-adrenal axis. First, the hypothalamus activates the sympathetic nervous system. The adrenal gland then secretes epinephrine and norepinephrine, which increase heart rate. The pituitary gland produces hormones that tell the adrenal gland to secrete cortisol, which is involved with the release of stored energy. The negative feedback loop comes into effect when the hypothalamus detects that the cortisol has reached a certain concentration, thus returning the body to homeostasis.

The Hypothalamus controls our stress responses. When a stress response is triggered it sends signals to either the adrenal medulla or the anterior pituitary gland. The short term responses produce the fight or flight response via the Sympathetic Adrenal Medullary System (SAM) considered the first shock response. The Hypothalamus will deal with the onset of a sudden or severe stress by stimulate the Adrenal Medulla to release adrenaline and noradrenaline. This will generally increase the heart rate, slows digestive activity, dilation of pupils, dry mouth and glucose is released

The autonomic nervous system controls cardiac, smooth muscle and the glandular tissue. It is vital in emergency and nonemergency (rest /digest). It is responsible for nearly all voluntary muscle movements as well as for processing sensory information that arrives via external stimuli including hearing, touch, and sight. The autonomic nervous system contains 2 subdivisions which are the sympathetic and parasympathetic. The general action of the sympathetic nervous system is to mobilise the body’s first or flight response (how the body reacts to perceive danger) by preparing the body to put out energy and to protect it from effects of injury. However, the parasympathetic nervous system restores the body a state of calm. It is a slow system and

The Glia cells have an important role they are the ones that clean up our dead neurons and any debris and carrying nutrients. They simply thought that they only supported the neuron. Now we understand

Did you know that the Parasympathetic and the Sympathetic systems both engage the same group of bodily functions, they regulate? “The action of the two systems are often but not always antagonistic (Nicholls et al. 316). The Sympathetic system activates without any conscious control of bodily responses to a perceived threat and prepares the body for intense physical activity (Fight or Flight). In addition, originates in the spinal cord; specifically in the lumbar regions and the thoracic. While the Parasympathetic system originates in the medulla and the spinal cord and controls the homeostasis, relaxing the body and inhibits or slows many high-energy functions, (Rest and Digest). The Parasympathetic and Sympathetic systems both innervate the same organs such as The Cardiovascular System- heart rate, The Pulmonary System- lungs, The Musculoskeletal System- muscles, The Gastrointestinal System- stomach and liver, The urinary System- bladder, pupils in the eyes and salivary

As humans, we have one of the most complex biological structures existing right inside of our heads, we call this structure our brain. Some of those building blocks in our brain to consider are developed by age 20, they include the 100 billion neurons we have. Among these neurons there are can be 100 trillion to 1 quadrillion connections between them. The other important part of the brain to inspect are glial cells which help essentially serve the brain as an immune system. There are three types glial cells, each with a unique job. Oligodendroglia helps our myelin sheath fire more quickly by proving insulation. Astroglia, and microglia are the two other types of glial cells and their job is to be the housekeeping of the brain by protecting

Human brain consists of billions of cells interconnected together, with each performing its separate functions. It consists of two explicit categories of nerves: neurons and glia cells. Neuron is a single nerve cell in the entire nervous system; which is electrically excitable cell that carries information after being processed via chemical or electrical signals. One of its key characteristics is that it does not undergo cell division. In addition, it maintains a voltage gradient for all the neurons across its membranes. Glia cells, on the other hand, its functionality is to maintain homeostasis.