and How it Fires Describe the basic physiology of a neuron. Detail the manner by which neurons fire action potentials and how neurons communicate with one another across synapses. Outline the process of how an action petential occurs and hoe it propagates down an axon. Explain how chemical transmission occurs at synapses and how this allows neurons to activate of inhibit one another. [Picture from "Answer to Neuron Structure"] Neurons are the basic units of the brain. Above is a picture
• Touch: Our sense of touch is mainly governed by a huge network of free-nerve endings and touch receptors located near or at the surface of the skin. These receptors combined with the free-nerve endings in the skin are known as the somatosensory system. They are activated by a stimulus, which in turn makes the neural membrane more permeable to sodium ions, thus allowing an action potential to occur (given that the charge exceeds the threshold). The impulse may or may not travel to the brain depending
Synaptic transmission is the process of the communication of neurons. Communication between neurons and communication between neuron and muscle occurs at specialized junction called synapses. The most common type of synapse is the chemical synapse. Synaptic transmission begins when the nerve impulse or action potential reaches the presynaptic axon terminal. The action potential causes depolarization of the presynaptic membrane and it will initiates the sequence of events leading to release the
that integrates the whole structure is the dendrites. Neurons' main role is to transmit information throughout the whole body. The whole structure of a neuron is responsible for the transmission process to occur. Neurons use electrical signals and chemical messengers to transmit information to the adjacent neuron,
Located in the nervous System region, the formation of Synapses begins in the Synaptogenesis stage. As Cohen-Cory (2002) noted that during the Synaptogenesis stage, Synapses are established, matured, and stabilized (p. 770). The beginning stages of the development, maturity, and stabilization of Synapses occurs in the Central nervous system (CNS). In the following manner, Synapses are established and matured in the CNS, Synapses stabilizes it neurons by trading off between the axons and dendrites
the nervous system. The concept of the neuron forms the basis of understanding cells and the nervous system. I recognize the importance of neurons (nerve cells), where the chemical excitation process created by the dendrites. Neuron communication also depends on resting potentials, where it is necessary that there are chemical contrasts that are necessary to create equilibrium. Additionally, in communication, the neurons require energy redistribution, and the neurons are useful when connections are
is caused by abnormalities in neurotransmission at synapses. Neurotransmitters are specific chemicals released from a neuron, which travel across neuron synapses to specific receptor sites. Low levels of neurotransmitters at synapses, have been found to cause low mood and depression. The re- uptake of the neurotransmitter into the synapse causes the neurotransmitter to become inactive. This means the level of the chemical messen... ... middle of paper ... ...red such as social
The synapse, as coined by Charles Sherrington in 1897, is one of the most influential discoveries in neurophysiology. Synapses are the junctions between a neuron’s axon and another neuron’s cell membrane, transmitting information about an action potential chemically or electrically. They are thus essential to neuronal function. The discovery occurred in part due to nineteenth century technological advances, such as the microtome, improved histological techniques, and the compound light microscope
) Describe the composition and function of the cell body. b) How are axons and dendrites alike? In what ways (structurally and functionally) do they differ? • The neuron cell body consists of a spherical nucleus with a conspicuous nucleolus surrounded by cytoplasm. The cell body of some neurons also contains pigment inclusions. It is the focal point for outgrowth of neuron processes during embryonic development. In some neurons, the plasma membrane of the cell body acts as part of the receptive region
so in order for glutamate to be an efficient neurotransmitter, a low external signal-to-noise ratio must be preset in order to prevent excitotoxicity which can damage and even kill nearby neurons. Glutamate must also need to be removed from the synapse or it must have to be resynthesized within the
the workings of the brain and to learn the effects of natural and unnatural substances on it. In order to look at chemical effects on the brain, one must first get an understanding for the chemicals as well as how the brain works to interpret and react to signals set out by these chemicals, rhythmically and physiologically. Several chemicals observed include: cocaine (and other chemicals), seratonin, and melatonin. Nature and life are full of rhythms. Rhythms in nature include: day and night
little more. Battery, also called an electric cell, is a device that converts chemical energy into electricity. All batteries contain an electrolyte, a positive electrode, and a negative electrode. There are two general types of batteries. Batteries in which chemicals cannot be reconstituted into their original form once their energy have been converted these are called primary cells. Batteries in which the chemicals can be reconstituted by passing an electric current through them in the opposite
A Critical Analysis of the Effects of Chemical Castration and Physical Castration on the Recidivism Rates of Sex Offenders Introduction This paper examines the effects of chemical castration and physical castration on the recidivism rates of sex offenders. Using theory integration or the multifactor approach, the findings reveal there are several factors influencing sex offender recidivism. Both chemical castration and physical castration have the potential to reduce the recidivism rates of
to water pollution. Problems we see with agriculture are applications of fertilizers, insecticides, and pesticides. We have made vast improvements in the types of chemicals we are using, as to how environmentally friendly they are. In 1985 the amount of fertilizer added to America’s fields was 11.5 million tons. Not only do these chemicals leech in to the soil, but they are also swept off the soils by rain and wind. When these fertilizers reach the water there is a sudden boom in plant growth. When
that make our planet warm enough for habitation are largely invisible. Even water vapor, the main constituent driving the greenhouse effect, is invisible, but whose existence can be inferred when it condenses as one exhales on a wintry day. The chemicals-such as dioxin, PCBs, pesticides, arsenic, DDT, and lead-that we litter our soils, atmosphere, and waterways with are also nearly invisible, especially at the concentrations that we, the users and consumers, are told are "acceptable." Microscopic
carefully clean up spilled chemicals. Some materials can spontaneously combust when mixed (this is especially true of nitrates and chlorates). For the same reason, use separate instruments (plastic spoons, mixing cups, etc) for different chemicals. Label your instruments so that you know what materials they have been in contact with. 3) Mix materials outdoors. Chemical explosives contain their own internal source of oxygen, and cannot be smothered. If you start a chemical fire indoors, it can be nearly
health reports. More and more reports are coming out on the effects of marijuana on the body. Just how harmful marijuana can be is questionable. Some health reports state that it is very detrimental to the body while others are explaining how chemicals extracted from the marijuana plant are being used as medication. The problem is, just what are the effects, and how bad is it for someone who uses this drug? I have picked this topic because I am very interested in the effects of marijuana on
each year in the United States. This is ten times more than was applied forty years ago. It is still unknown as to what type of exact effects these chemicals may have on individuals. Some farmers that have been using pesticides in their fields and developed leukemia are finding that the cause of their disease is from inhaling pesticides. These chemicals are still in use today and most of them have never been tested for the short or long-term effects that they may have on humans. Each year there
Evaluation of the Financial Performance of a Chemical Company The Lee Chew Cheng Wong Chemical Company produces high quality speciality chemicals, and it exports around 85% of its output to many countries and regions. Since the establishment in the mid 1980 this company has emphasized the shareholder value. To keep this focus, a new Chief Executive Lee Shan Loke Teo has proposed a lot of new policies. This assignment evaluates the financial rations with Sun See Chemical Company and average industry, and presents
Chemical Control Agents Used Against the Gypsy Moth The gypsy moth (Lymantria dispar) is a highly disruptive species that can, and has played a distinctive role in the lives of many organisms. Included in these organisms are various deciduous trees and shrubs, wildlife species that share the same environment, and even humans. The gypsy moth destroys the beauty of woodlands via defoliation, alters ecosystems and wildlife habitats, and disrupts our own lives. It should therefore come as no surprise