answersLogoWhite

0

Nerves

Nerves are thread-like structures that form a network of pathways that transmit information from the brain to the body and the body to the brain, in the form of electrical impulses.

1,605 Questions

What is the area between neurons across which nerve impulses travel?

no, synapse. node of ranvier is between axon and dendrites

Where are the most nerve endings in your body?

Areas that are more associated with sensory systems such as hands feet have more nerves

What are the 3 main parts of neuron or nerve cells?

  • Cell body (also known as soma)
  • axon
  • myelin sheath (not present in all neurons)
  • synapse (at the end where neurotransmitters are released to. Not really a part as it is not technically attached to the neuron)
  • dendrites
  • axon terminal

What are association neurons?

I think you could mean association fibres - the fibres (also called axons) being the long thin part of a neuron? Association fibres connect various areas of the brain to one another, and act as a kind of relay station where incoming sensory information is compared with previous experience of that information, and then integrate the appropriate motor response. For example, imagine you're driving along the road when you see a traffic light up ahead turn to amber. So the sensory input is visual information from your eyes; it arrives at the appropriate 'relay area' in your brain, where information is quickly brought up from the learning areas reminding you that an amber light means it's gonna be red by the time you reach it, so you'd better start slowing down; another visual message supplies the information of how far you are away from the light, and yet another how fast you are driving; now some more 'learned' information comes in, telling you (based on your previous driving experiences) things like how many seconds it'll be before you reach the light, and how hard to need to press on the brake pedal to be able to stop safely and in time. In the meantime, messages have been drafted & sent to the motor cortex: the rough draft is that the muscles in your leg & foot are gonna have some work to do very soon; the motor cortex responds by sending a message back to the association area: "OK, ready when you are; this is the current state of play as regards the precise position of foot and leg right now - so how hard are we gonna have to work?" So now the association fibres have all the information they need; they integrate all of these messages so that they the final message sent out via the motor association area to the motor cortex can tell those muscles exactly how hard your foot needs to press on the brake pedal to stop the car in the precise spot it needs to stop. This is a very simplified description of the incredibly complex work done by the association fibres to help you carry out just one little action.

What part of the brain routes nerve impulses from your senses?

Most nerve impulses from our senses are routed through the: Thalamus-

What chemicals are released when a nerve impulse arrives at the synapse?

Neurotransmitters. There are several hundred different neurotransmitters used by different types of nerves in different parts of the body, a few are:

  • acetylcholine
  • dopamine
  • serotonin
  • glutamate
  • aspartate
  • D-serine
  • γ-aminobutyric acid (GABA)
  • glycine
  • nitric oxide (NO)
  • carbon monoxide (CO)
  • hydrogen sulfide (H2S)
  • norepinephrine
  • epinephrine (adrenaline)
  • histamine
  • phenethylamine
  • N-methylphenethylamine
  • tyramine
  • 3-iodothyronamine
  • octopamine
  • tryptamine
  • somatostatin
  • substance P
  • cocaine and amphetamine regulated transcript, opioid peptides[9]
  • adenosine triphosphate (ATP)
  • adenosine
  • anandamide
  • β-endorphin
  • vasopressin
  • dynorphin
  • oxytocin
  • etc.

How many touch receptors are in the average person?

The average human skin contains approximately 5 million touch receptors, including various types such as Meissner's corpuscles, Pacinian corpuscles, and Merkel cells. These receptors are distributed unevenly across the body, with areas like the fingertips and lips having a higher density. This intricate network enables us to perceive a wide range of tactile sensations.

How are chemical signals sent between neurons?

The nervous system uses mainly neuron cells to communicate. The neuron communicated "electrically" through what is called an action potential (basically an electric "signal" that travels along a neuron), this is generated when an appropriate stimulus (on a cellular level) brings the axon hillock region of the neuron to an electrical potential difference (between inside and outside of cell) of -55mV. This triggers the electrically triggered Na+ (sodium ion) gates to open, this causes a massive flow of a + charged ion into a region of the cell, making it more positive there, which triggers another electrically gated Na+ channel right next to it (closer to the "end" of neuron), then the flow of Na+ ions in to that region open the gates next to it....ect. This repeats until the "signal" has traveled all the way down to the "end" of the neuron. The "signal" is really information.

Neurons can use chemicals to communicate too, these chemicals are called neurocrines. They can work like hormones (long distance commun. and travel through the blood stream), or they can work on a very short distance (neurotransmitters). I will give an example using AcH (acetyl choline, a neurotransmitter used in many cases, including muscle contraction). When you think about moving your arm, action potentials are generated in your brain and travel along other neurons (through spinal cord, and through/into arm) and end up right above certain parts of muscle cells. they stop just above but don't touch your muscles. then as the action potential reaches the end of the neuron, the "electrical signal" is converted into a chemical signal (by devices in the neuron looking for specific voltages before "production" begins). Then this chemical (AcH or ACh) is released from the end of the neuron right over the muscle cell (this region is called the synaptic cleft). The AcH travels a very very short distance and then binds to receptors on the muscle cell, stimulating the muscle cell to begin the contraction process, the action potentials are coming one after another as fast as they can (there is a limit). so when you hold you arm out, your muscles not getting a continual signal telling it to stay contracted, but a series of signals, and so in the space between the neuron and muscle cell a chemical is released (by the muscle cell) that's breaks down the AcH in such a way that the muscle cell thinks its getting a continuous signal. I got a little off topic but i wanted to explain why the space was there.

Can neurons repair themselves?

Certain neurons can repair themselves while others can't. Neurons that can repair themselves are refreed to as white matter. The reason white matter can repair itself is because the axons of white matter are myelinated. The axons of neurons in grey matter on the other hand, cannot repair themselves because they are unmyelinated.

How are olfactory neurons classified structurally?

Neurons are classified by the direction they move.

What neurons receive information from sensory organs?

Dendrites are the part of the neuron specialized to receive information from other neurons and the axon transmits signals to other neurons or to muscles or glands.

What do neurons look like?

Although neurons are very diverse and there are exceptions to nearly every rule, it is convenient to begin with a schematic description of the structure and function of a "typical" neuron. A typical neuron is divided into three parts: the soma or cell body, dendrites, and axon. The soma is usually compact; the axon and dendrites are filaments that extrude from it. Dendrites typically branch profusely, getting thinner with each branching, and extending their farthest branches a few hundred micrometres from the soma. The axon leaves the soma at a swelling called the axon hillock, and can extend for great distances, giving rise to hundreds of branches. Unlike dendrites, an axon usually maintains the same diameter as it extends. The soma may give rise to numerous dendrites, but never to more than one axon. Synaptic signals from other neurons are received by the soma and dendrites; signals to other neurons are transmitted by the axon. A typical synapse, then, is a contact between the axon of one neuron and a dendrite or soma of another. Synaptic signals may be excitatory or inhibitory. If the net excitation received by a neuron over a short period of time is large enough, the neuron generates a brief pulse called an action potential, which originates at the soma and propagates rapidly along the axon, activating synapses onto other neurons as it goes.

source : a fragment of the whole article about neurons from Wikipedia.

Which cranial nerve is the largest in diameter?

The X craneal nerve (vagus), it goes all the way to your diafragm

What counteracts nerve agent poisoning?

Atropine and 2pam chloride. This is in a kit that the us military gives out. Not sure of the doses, but I do know that the needles for the injection are HUGE. I know this, because I am currently in the military and this has been something that we are taught from basic training and continuously throughout our careers.

Parts and function of neuron?

the function of neurons is to receive information, process it, and pass it on to other neurons, or muscles or endocrine/exocrine glands. I realize 'receive information, process it, and pass it on' is a giant and amorphous description, but the description of the behavior of organisms with neurons is also giant and amorphous.

What causes a constant 'pins and needles' sensation down left arm?

You should always see your doctor with these symptoms. Most of the time it's stress through the neck and shoulder area and when under stress the muscles freeze up (like a knot.) A good soak in the tub with Epsom Salts will certainly help, and rub your neck and shoulders well with A535. If you are still having this problem then please see your doctor immediately.

If the pins and needles go along with a heavy chest or jaw pain call 911! It may be due to anxiety due to stress (many patients think they are having a heart attack and it turns out to be anxiety.) It's better to be safe than sorry.

NumbnessNumbness and tingling and parasthesia on the left side of the body means that there may be an abnormality in the right side of the brain.It can be a neurological pathology like motor neuron disease,TIA or stroke or autoimmune condition like multiple sclerosis in which the immune system attacks the central nervous system (CNS), leading to demyelination.It can be diagnosed by MRI brain and MRS of the brain.

Other possibilities are vit B12 deficiency,diabetes, hypothyroidism, hypoparathyroidism or peripheral nerve trauma or compression.

If tingling is there only on the left half of the body,it means a right side pathology of the brain.So I feel that clinical evaluation from a neurologist is necessary to rule it out.

Is it possible to have brain transplantation?

No. People cannot live without the brain, because the brain controls your body.

You won't be able to breath, move, eat or do ANYTHING, not even swallow, you would be useless without a brain.

How is the electrical charge inside the neuron?

Neurons send messages electrochemically and all chemicals in the body are electrically-charged. When neurons inside the body are electrically-charged, they are called ions. When a neuron is at rest, or not electrically-charged, the inside is negative and the outside is positive.

What nerve is carrying the afferent and efferent impulses during the patellar reflex?

The nerves innervate the quadriceps. The afferent nerves are the muscle spindles and the efferent are the motor neurons.

Can a pinched nerve cause a stroke?

d test for pinched nerve not pinched finger numb

How does a synapse work?

There are several types of synapses in the body. The most commonly discussed type is the chemical synapse, but other types of synapses include electrical synapses and immunological synapses. Because chemical synapses are the most commonly discussed synapses in general, that's probably what this question is referring to.

A chemical synapse is a small gap, or commonly referred to as a connection, between two cells that allows for the first cell (the presynaptic cell) to communicate with the second cell (the postsynaptic cell) through a chemical signal. These chemical signals are called neurotransmitters, and once they are released by the presynaptic cell, they act on the postsynaptic cell through specialized protein molecules called neurotransmitter receptors.

The actions triggered by a neurotransmitter binding its receptor on the postsynaptic cell are highly varied. They vary according to the type, quantity, and frequency of neurotransmitter release, the specific receptor involved, the type of cell that is receiving the neurotransmitter signal, among other things. For example, a neurotransmitter called glutamate typically causes activation of the postsynaptic cell, while a neurotransmitter called GABA typically inhibits postsynaptic cells. Likewise, if the postsynaptic cell belongs to a gland, then activity in that cell may promote secretion, while inhibition may hinder secretion. If the postsynaptic cell is a muscle fiber, then activation triggers muscle contraction, while inhibition causes relaxation.

A synapse is a connection which allows for the transmission of nerve impulses. Synapses can be found at the points where nerve cells meet other nerve cells, and where nerve cells interface with glandular and muscular cells. In all cases, this connection allows for the one-way movement of data. The human body contains trillions of synapses, and at any given time, huge numbers of these connections are active.

What is the job of nerve tissue?

It carries electrical signals that affect muscle tissue.

The fourth primary type of tissue is nerve tissue. Nerve tissue is found in the brain, spinal cord, and accompanying nerves. The function of the nerve tissue is to move and coordinate bodily functions.

Nerve tissue is composed at two subtypes of tissue:

1. Specialized cells called neurons (nerve cells) receive stimuli and conduct impulses to and from all parts of the body

2. . Neuroglial or glial cells. Unlike bone, which is rigid, nerve tissue has a wet noodle-like compactness, and therefore must be supported by connective tissue. Some glial cells support neurons in the brain and spinal cord by entwining around them, while others bind neurons to other connective tissue. Both the brain and spinal cord are covered by three thin layers of tissue called meninges: the dura mater (external layer); the arachnoids (middle layer); and the pia mater (internal layer).