Axon

the precise sequence of contractions of the various muscles that will be required to set the volleyball over the net. A motor command is generated in the primary motor cortex (M1) coding how much force each muscle group must exert is sent down the axons of giant pyramidal neurons originating in M1 to John’s brainstem where 90% will decussate below the medulla before continuing down the spinal cord. The signal triggers coordinated movement via muscle synergies and with the help of the…

auto immune disease which affects neurons of the central nervous system. A neuron consists of three main parts: an axon, dendrite, and a cell body. The axon is usually myelinated with a substance known as the myelin sheath, created by oligodendrocytes. This consists of twenty percent protein and eighty percent lipid. Each oligodendrocyte creates enough myelin to wrap around several axons. The periodic gaps between the neurons are known as nodes of Ranvier, where the nerve signals jump from…

Boston is one of the best cities in the world with some of the most incredible people and the best culture. With that said, not every city is made for the Olympic games. Boston for example; it is recently ranked as the 34rd best city to live in, in the world according to TheGuardian.com (theguardian). Though a great city, Boston is not a good city to host an event such as the Olympics. With Boston’s uniquely difficult navigation and asymmetrical lay-out, Boston would not be able to handle the…

1. Distinguish between afferent and efferent nerves. Afferent nerves are the sensory nerves. They carry information from the world to the brain and spinal cord. Efferent nerves are the motor nerves they carry information out of the brain and spinal cord to other parts of the body. Afferent nerves take in information and efferent nerves carry out information. 2. Study Figure 2.1. What makes up the Central Nervous System (CNS)? The central nervous system is made up of the brain and…

underneath the external grey tissue. It’s made out of wads of either wires or axons which associate billions of neurons and convey electrical indications between them. A group drove by neuroscientist Rex Jung, from the University of New Mexico, gathered information using a MRI procedure called diffusion tensor imaging. This is what enables researchers to see through a skull of a living individual and outline the pathways of the axons by following the water’s movements…

Earthworm Action Potential Conduction Velocity: The Effects of Various Salts and Neurotransmitters When it comes to performing action potential experiments within the lab, the giant nerve fibers of an earthworm are an important tool for success. They yield a high success rate when compared to other organisms (Kladt, Hanslik, & Heinzel, 2010), and provide a more ethical means of testing how various neurotransmitters affect action potentials, instead of direct use on humans for pharmaceutical…

In order for motor neurons to communicate with the skeletal muscle fibres of my fingers, a synapse is formed between them, known as a neuromuscular junction. The neural and muscular sides of the NMJ have different roles to play. The motor neuron’s axon terminal, along which nerve impulses travel, ends in a series of synaptic end bulbs, full of synaptic vesicles, floating in cytosol. Within these vesicles are the precious messengers, molecules of the neurotransmittor, acetycholine (ACh). Across…

ALZHEIMER’S DISEASE An estimated 5.2 million Americans currently are afflicted with Alzheimer’s disease, usually called AD. Age is the highest risk factor. From studies conducted by the Center for Disease Control and Prevention we learn that AD is now the sixth leading cause of death in this country, but it leaps to fifth place for those who have already reached the age of sixty-five. By age eight-five an estimated thirty-two percent of Americans have contracted full-blown AD. Women are at far…

shooting an electrical impulse down a wire (on). It has a cell body, along little wire (the "wire" is called an axon), and at the very end it has a little part that shoots out a chemical. This chemical goes across a gap (synapse) where it triggers another neuron to send a message. There are a lot of these neurons sending messages down a wire (axon). By the way, each of these billions of axons is generating a small amount of electrical charge; this total power has been estimated to equal a 60…

Fyodor Dostoyevsky created the novel, Notes From Underground, holding insightful thoughts on the purpose and meaning of life. Within the novel, Dostoyevsky creates the character, the Underground Man. He laments human’s inconsistencies and their inability to grasp the meaninglessness of existence; while they work tirelessly to exert control over their uncontrollable environments. Human desire for power is epitomized in their attempts to rebel against the physiological laws of nature that govern…