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The speed of impulse in a reflex arc can vary, but it is usually very fast, allowing for quick responses to stimuli. In general, impulses can travel at speeds of up to 100 meters per second along myelinated nerve fibers.
Nerve impulses are signals carried along nerve fibers. These signals convey, to the spinal cord and brain, information about the body and about the outside world. They communicate among centers in the central nervous system and they command your muscles to move.Nerve impulses are electrochemical events. Observed as an electrical event, a nerve impulse is called an action potential (AP) because it involves a change in electrical potential that moves along the nerve cell. It can be measured as an electrical potential difference between the inside and the outside of a nerve fiber. That option has not been generally available to the beginning student. Instead, the nerve impulse has ordinarily been observed as a voltage change along the outside of the sciatic nerve of the common grass frog, Rana pipiens.Rana pipiens and its relatives have long been favorite subjects for introducing students to the physiology of nerve and muscle. For serious investigations, use of frogs will continue to be justified, but the consumption of this resource for routine teaching ought now to be reduced, for at least three convincing reasons:Computing power has become so effective and so generally available that some essential concepts of nerve electrophysiology can as well or better be conveyed by simulation and example rather than by use of live material.In the frenzy of trying to make the real specimen perform properly during a student exercise, important ideas are often omitted or are lost because of equipment failure or operator ineptitude.Frog populations worldwide appear to be diminishing at an alarming rate, and biologists, of all people, ought not abet this decline.This instructional module shows, by illustrations and text, some of the essential features of nerve impulse propagation, a phenomenon that many students find especially difficult to visualize. The lesson is based on observations made during external recording from the sciatic nerve of Rana pipiens.Topics 1-11 afford a review of some aspects of single-neurone transmembrane characteristics. With this background,the student is prepared to appreciate the whole-nerve behavior illustrated in topics 12-30. The latter are based on actual cathode-ray-oscilloscope records of the type obtained by students in a laboratory course.this info was taken off http://www.bio.fsu.edu/easton/intro.html
Acetylcholine is NOT the only chemical transmitter released by nerve endings. There are literally dozens. Ach is only the first discovered. Others include: glutamate, aspartate, serine, gamma-aminobutyric acid, glycine,dopamine, norepinephrine, epinephrine (adrenaline), histamine, serotonin, melatonin, adenosine, anandamide, True ACh was discovered first and is not the only neurotransmitter released, BUT Acetylcholine is basically the one of most important in producing an impulse.
ATP provides the energy needed for cells to carry out various functions such as metabolism, growth, and movement. It serves as the primary energy currency of the cell, powering essential processes like muscle contraction, nerve impulse transmission, and protein synthesis.
Each ear has three main nerves: the vestibulocochlear nerve, the facial nerve, and the vestibular nerve. These nerves are responsible for hearing, balance, and facial movement.
The electrical impulse in a nerve cell begins when ions move through the cells surface through ion channels.The nerve impulse.A nerve impulse is a wave of excitation that quickly travels within the surface of a neurone (nerve cell). This nerve impulse usually travels on certain parts of the nerve cell: on a dendrite or an axon. Within a neurone the first event depends on the type of 'nerve impulse'; there are two important types:1- nerve impulses generated at dendrites2- self propagating nerve impulses (action potentials) that travel along the axonNerve impulses generated at dendrites.Dendrites feed into the 'cell body' (soma) of a neurone. Nerve impulses that are generated in these dendrites travel toward the cell body.A sequence of events occur at the surface of a dendrite when the nerve impulse is sparked. The first event is transduction; this involves the transformation of one form of energy outside the dendrite into electrical energy within the dendrite.Nerve impulses that travel along axons.Nerve cells often have many dendrites but often only have a single axon. The essential difference between the two parts of the nerve cell is:- in dendrites electrical impulses travel TOWARDS the cell body of the neurone- in the axon the electrical impulses travel AWAY from the cell body of the neuroneThe nerve impulse that travels along an axon begins at the 'base of the axon', where the cell body and axon merge. This site is called the 'axon hillock' and is found to be the site where the first event in the formation of a nerve impulse actually occurs. Again, the first event is transduction at the axon hillock.Conclusion; the first event.For both of the cases above, and for virtually any other case, the nerve impulse begins with a process of transduction. The electrical nerve impulse begins once the first 'ions' leave or enter the nerve cell. Usually sodium ions enter, sometimes calcium ions are the firs to enter, sometimes potassium ions are the first to leave.
The nerve's endings are near to other nerve endings, when the potential of the potassium ion that is released is sensed by the other nerves they all might send an impulse to their other ends and the situation could be repeated.
The speed of impulse in a reflex arc can vary, but it is usually very fast, allowing for quick responses to stimuli. In general, impulses can travel at speeds of up to 100 meters per second along myelinated nerve fibers.
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A ray of light can travel in any direction, so an infinite number.
Nerve tissue, but it does much more than that - there are many nerve circuits that have no connection to the brain, performing their functions locally and unconsciously.
Homeostasis requires many different types of cells but the main cell that ensures that homeostasis is maintained is the nerve cell which forms your sensory neuron this helps by sending a nerve impulse to the hypothalamus of your brain or the islets of langerhan in the pancreas this nerve impulse helps send a message to the stated parts of your body telling them to take corrective measures to stabilize your body's internal environment
how fast is lightning? well it's about 3x the speed of sound...im just making a logical guessNew AnswerThe slowest nerve impulses are mostly those involving pain and may travel at about 2 meters per second. This is why you may not immediately feel the pain when you stub your toe. On the other hand, some nerve pulses travel at speeds of up to a few hundred meters per second. The speed of the impulse transmission depends on many variables, such as the diameter and type of the nerve fiber, whether it has a myelinated sheath, etc.
The NeuronThe cells that carry information through your nervous system are called neurons, or nerve cells. The message that a neuron carries is called a nerve impulse. The Structure of a Neuron:The structure of the neuron enables it to carry nerve impulses. A neuron has a large cell body that contains the nucleus, threadlike extensions called dendrites, and an axon. The dendrites carry impulses toward the neuron's cell body. The axon carries impulses away from the cell body. Nerve impulses begin in a dendrite, move toward the cell body, and then move down the axon. A neuron can have many dendrites, but it has only one axon. An axon, however, can have more than one tip, so the impulse can go to more than one other cell. Axons and dendrites are sometimes called nerve fibers. Nerve fibers are often arranged in parallel bundles covered with a connective tissue, something like a package of uncooked spaghetti wrapped in cellophane. A bundle of nerve fibers is called a nerve.Kinds of Neurons:Three kinds of neurons are found in the body-- sensory neurons, interneurons, and motor neurons.A sensory neuron picks up stimuli from the internal or external environment and converts each stimulus into a nerve impulse. The impulse travels along the sensory neuron until it reaches the interneuron, usually in the brain or spinal cord. An interneuron is a neuron that carries nerve impulses from one neuron to another. Some interneurons pass impulses from sensory neurons to motor neurons. A motor neuron sends an impulse to a muscle or gland, and the muscle or gland reacts in response.How a Nerve Impulse TravelsThe Synapse:What happens when a nerve impulse reaches the axon tip at the end of a neuron? At that point, the impulse can pass to the next structure. Sometimes the structure is a dendrite of another neuron. Other times, the structure is a muscle or a cell in another organ, such as a sweat gland. The junction where one neuron can transfer an impulse to another structure is called a synapse. (SIN aps). How an Impulse is Transferred:For a nerve impulse to be carried along at a synapse, it must cross the gap between the axon and the next structure. The axon tips release chemicals that carry the impulse across the gap.You can think of the gap at a synapse as a river, and an axon as a road that leads up to the riverbank. The nerve impulse is like a car traveling on the road. To get to the other side, the car has to cross the river. The car gets on a ferry boat, which carries it across the river. The chemicals that the axon tips release are like the ferry, carrying the nerve impulse across the gap.
Impulse economy has 240 pages.
When a single neuron sends a strong enough impulse to a muscle, it can cause multiple muscle fibers within that muscle to contract. The specific number of muscle fibers that contract will depend on factors like the size of the motor unit and the intensity of the signal from the neuron.
Sound moves in all directions, meaning it propagates outwards in a spherical pattern from its source. This allows sound to travel in all directions from where it originates.