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Nervous System
This category is for questions about the mechanical and chemical process of reactions to internal and external stimuli, ranging from the brain down to the spinal cord, and all nerves, cells and tissues in between.
3,047 Questions
What type of nerves fibers make of each of the following sensory nerves?
Well, there are really only three types of fibers, but they all have different sub-classes to them. A, B, and C. A and B fibers are myelinated, and C fibers are unmyelinated. A fibers are broken down further by conduction velocity into 4 main groups, alpha, beta, gamma, and delta. In general a chart of these fibers would look something like this..
A(alpha), largest and fastest velocity, acts as motor and sensory fibers
A(beta), next largest, acts as motor and sensory.
A(gama), next largest, acts as motor only.
A(delta), next largest, acts as sensory only.
B, smaller than A fibers, only acts a motor.
C, smallest, acts as motor and sensory. In general, the A class of fibers are related to muscles(extrafusal and intrafusal fibers), A(delta) sensory fibers relay touch, pressure, pain, and temp, B motor fibers are for the autonomic system, while C sensory fibers are also for pain and temp. Note. Sometimes the sensory fibers are classified by a roman numeral system from I to IV. They are the same fibers, just numbered differently. They look like this... A(alpha) = Ia
A(alpha) = Ib
A(beta) = II
A(delta) = III
C = IV Hope this helps...
Daniel {| |- | A 1-20 5-120 0.3-0.5 B <4 3-15 1.2 C 0.3-1.5 0.6-2.5 2.0 |}
Which part of the neuron is capable of generating an action potiential?
When a neuron gets excited from a neighboring cell (from neurotransmitters) it gets 'leaky' to certain ions like sodium, potassium, calcium and chloride - and in doing so its state of electrical excitability changes. If it changes by just the right amount then special proteins called 'voltage-gated ion channels' will open allowing a huge influx of even more ions (usually sodium) causing a wave of electrical charge to flow away from the cell body down its axon to its axon terminal - where it will then release its neurotransmitters.
Why is the nervous system necessary?
Cholesterol is needed by the nervous system to insulate neurons and prevent damage that would interfere with the normal function of the nervous system.
Calcium also plays an important role in the central nervous system, especially within the brain. Calcium ions are essential in converting electrical impulses into chemical signals in the brain. The presence of calcium ions in the synaptic vesicles triggers the neurotransmitters to be released into the synaptic cleft. The signal can then cross the cleft and fuse with the dendrite on the other side, effectively helping to pass the signal to wherever it needs to go in the brain.
What neuron carries impulses from receptors to the central nervous system?
Neurons that convey sensory information are called 'sensory neurons' or "afferent neurones"
What is the function of the medula oblongata?
it extend the spinal cord through four fifth of the spinal column
What is way you can keep nervous system healthy?
The following activities, if maintained on a life-long basis, can help keep the nervous system operating at peak efficiency:
- eating a proper diet low in fat and high in fiber
- maintaining a healthy weight
- consuming proper amounts of good-quality drinking water
- getting adequate rest
- engaging in regular exercise
- not smoking or taking illegal drugs
- drinking only moderate amounts of alcohol (if at all)
- reducing stress levels
What is the most important part of the digestive system?
Ice cream is the most important absorbing organ in the digestive system.
Describe how schwann cells form the myelin sheath and the neurolemma encasing the nerve processes?
The Schwann cells wrap themselves tightly around the axon like a jellyroll. During the wrapping process, the cytoplasm is squeezed from between adjacent layers of the Schwann cell membranes, so that when the process is completed a tight core of plasma membrane material encompasses the axon. This wrapping is the myelin sheath. The Schwann cell nucleus and the bulk of its cytoplasm end up just beneath the outermost portion of its plasma membrane. This peripheral part of the Schwann cell and its exposed plasma membrane is the neurilemma.
What body parts work together in the nervous system?
Your central nervous system controls your entire body via the spinal cord.
Which part of the nervous system regulates breathing?
The answer to this one is medulla:))))))))(((((((((
What kind of fibers are found in spinal nerves?
An axon is a nerve fibre, "a single process extending from the cell body of a neurone and carrying nerve impulses away from it".
A nerve bundle is made up of hundreds or thousands of axons. A good factsheet can be found at www.ivy-rose.co.uk/Topics/Neurons.htm
The cranial nerve responsible for chewing is?
Trigeminal V: a mixed nerve responsible for the chewing of food and sensations in the face, scalp, and teeth and the contraction of chewing muscles.
What are the factors involved in the transmission of a nerve impulse?
action potational. volage change, threshold etc
How does the circulatory affect the nervous system?
the blood in your circulatory system is connected to your brain there for it is also connected to your nerves because most of your body has nerves that will tell your brain is something is wrong.
What nervous center controls the internal organs?
The brain is the part of the peripheral nervous system that controls glandular activity and the muscles of the internal organs.
How many nerve cells make up the nervous system?
Only one but there are several divisions of it such as central vs peripheral or sympathetic vs parasympathetic nervous system. It's all one but different ways of dividing it up to make sense of it.
Is the sympathetic or parasympathetic involved in pupillary response?
the sympathetic nervous system (SNS) is a very important part of the autonomic nervous system. the SNS is well known for its role in the fight-or-flight response in the body. among the effects it has are: bronchodilation, increased heart rate, increased metabolism and dilated (increased diameter) pupils. the reason why pupils become dilated during SNS activity is because dilated pupils allow more light to enter the eye and it also increases the visual field - remember this is a fight-or-flight response, our responses to perceived threats are heightened and our senses are really alert.
the parasympathetic system on the other hand functions in time of rest and digestion. the PNS is therefore most active during our relaxed states.
sympathetic.
What is a group of drugs that slow down the nervous system?
There are many drugs that can slow down the body but they don't come into affect immediately
What is the difference between spinal column and vertebral column?
because during the growth of human beings the vertebral column outgrows the spinal chord. that's why we don't find the spinal cord starting from lower lumbar region where lumbar puncture is done.
Are the lungs part of nervous system?
No. It is part of both the respiratory and circulatory system. The parts of the Nervous System are:
Brain:
-Cerebrum
-Cerebellum
-Brain Stem
Neurons:
-Sensory Neuron
-Interneuron
-Motor Neuron
Spinal Cord
What happens if the sensory nerve is cut?
Cutting the optic nerve would lead to loss of vision in the affected eye.Damage to either optic tract would lead to loss of HALF the vision in in either eye (due to the crossing over of tracts in the optic chiasm). so you would loose half the visual field in either eye. (neoroscience student).
