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What is a disadvantage of unmyelinated nervous tissue when compared to myelinated tissue?
Wiki User
∙ 14y ago
Unmyelinated tissue is substantially slower in conducting impulses along the axon. With myelinated axons, the action potential (impulse) jumps from node to node greatly increasing the speed of the impulse.
Wiki User
∙ 14y ago
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Is white matter dense in myelinated axons?
Yes White matter is the part of the nervous system that is dense is myelinated axons
What nerve cells can you use to distinguish colors?
It depends on the tissue. Most nerves are too small to see individually, but there are bundles that can be viewed with the naked eye or a good dissecting microscope. Nerves can be myelinated, which means that they coated with a fatty layer to speed signal transmission. Most peripheral nerves and those not in the cortex of the brain are myelinated and thus appear white. Unmyelinated nerves are grayish, which is where the term "gray matter" comes from.
The axons of some neurons have an insulating coating called?
This is called myelin or myelin sheath. It's made mainly from fat with a few proteins in it, and is produced by oligodendrocyte cells in the CNS and schwann cells in the peripheral nervous system. It speeds up nerve signalling by allowing action potentials (the electric currents that make up nerve impulses) to skip between the gaps in the myelin (nodes of ranvier). In unmyelinated axons, sodium and potassium channels have to create the voltage differences at every single step along the nerve. (Say for example 100 times per nerve). Myelinated neurones only need to create these voltage differences at the nodes of ranvier (where sodium and potassium ion channels are located on myelinated neurones) Say for example there are 10 nodes of ranvier on a myelinated axon. The unmyelinated axon must create this voltage difference 10 times more frequently than the myelinated axon, hence the nerve impulse travels 10 times faster in a myelinated axon. (Based on the random numbers I used. In real life the numbers may be wildly different, but they still work in this way).
What describes the autonomic nervous system?
The nervous system (NS) can be divided into the central nervous system (CNS) which is the brain and spinal cord and the peripheral nervous system (PNS) which is the rest of the body. One of the general functions of the NS is Motor function. Motor function uses peripheral neurons so this particular function belongs to the PNS. Motor functions can be divided into two categories: (1) As motor functions of the Somatic Nervous System and (2) as motor functions of the Autonomic Nervous System. The Somatic nervous system is voluntary and controls skeletal muscle. The autonomic nervous system, or ANS, is that part of the peripheral nervous system that is involuntary. The ANS controls and regulates smooth muscle, cardiac muscle and glands. Most neuron axons in the ANS are unmyelinated and myelinated axons are rare. It's not possible to describe the ANS without also describing the SNS and mentioning at least one of the functions (Motor function)of the nervous system. You need to see how they all fit together.
How do myelinated nerves conduct nerve faster than unmyelinsted nerves?
With the myelinated nerves, the electrical signal jumps from one space between the myelin to another making the signal to travel faster while the unmyelinated nerves have electrical signals that has to travel all the way through without jumping.
What is myelinated nervous tissue?
White matter
Which neuron is never myelinated?
Neurons that do not have a myelin sheath must use continuous conduction, which is slower. These are the smaller axons of the CNS, as well as some types of fine sensory fibers, such as olfactory nerves.
Are muscles and glands myelinated?
Muscles and glands are not myelinated. It is the axon of a neuron that is myelinated. The myelin forms a layer called myelin sheath that makes the nervous system function properly.
Which type of cell produces the myelin covering around the axon of a neuron?
In the central nervous system, neuronal axons are myelinated by oligodendrocytes. In the peripheral nervous system axons are myelinated by Schwann cells.
Is white matter dense in myelinated axons?
Yes White matter is the part of the nervous system that is dense is myelinated axons
What type of nervous system conduction occurs in myelinated axons?
Saltatory Conduction
What system does White matter refer to myelinated fibers?
central nervous system (CNS)
White matter of the nervous system is composed of?
White matter in the nervous system is caused when the axons in the area are myelinated. This means that the axons have a fatty protein covering to provide insulation. The myelin sheath is composed of special cells calls Schwann Cells.
Does Gray matter contain collections of unmyelinated fibers and cell bodies in the central nervous system?
True
Which tissue is reinforced by white fibers only?
Myelinated axons in the central and peripheral nervous systems.
How does conduction differ on myelinated vs unmyelinated axons?
Very simples, myelinated axons have a myelin sheath! These are produced by the schwann cells in the Peripheral Nervous System and oligodendrocytes in the Central Nervous System. The myelin sheath is made out of lipids (fats) and proteins. The benefits of a myelinated axons is a faster transmission of an electrical impulse and also insulation. The breakdown of a myelin sheath from a medical background results in Demyelination.Tortora, G, Derrickson, B (2009) Principles of Anatomy and Physiology, Wiley, Asia, 12th Edition, Volume 1, Pages 416-423Hope this helps!
What is the function of white mater in the spinal cord?
White and grey matter are essentially made up of bundles of nerve fibers (called neurons) that convey nerve impulses between the peripheral nervous system and the central nervous system. The major difference between white and gray matter within the spinal cord is that white matter is primarily composed of myelinated nerve fibers, while the nerve fibers of gray matter are not. Myelinated nerve cells tremendously increase the speed at which the action potential (nerve impulse) moves along the neurons axon. The job of the neurons that make up white matter is to either convey an action potential from a sensory receptor to the central nervous system, or, from the central nervous system out to an effector (such as a muscle or tissue). These neurons are called sensory neurons and motor neurons respectively. Gray matter consists of unmyelinated neurons, called interneurons. Their main duty is to provide communication between the peripheral and central nervous systems. Think of interneurons as a bridge linking two regions together. For unmyelinated neurons, the speed at which an action potential can propagate down the cell's axon is far less than that of the myelinated neurons of white matter.
