How is the myelination pattern different in CNS and PNS?
In CNS (central nervous system) oligodendrocyte is responsible for myelination of neuronal axons. In PNS (peripheral nervous system) myelin sheath is formed by Schwann cell. in contrast to oligodendrocyte, one Schwann cell provide myelination for one axon (actually only a segment of one axon).
How does this process differ in the CNS and PNS?
The CNS consists of the brain and spinal cord, while the PNS includes all other nervous system tissue. All sensory receptors, sensory neurons and motor neurons are part of the PNS.
How does myelination occur in PNS?
Schwann cells in the peripheral nervous system (PNS) and oligodendrocytes in the central nervous system (CNS) form myelin by wrapping their cell membranes around axons to form a multilayered membranous sheath that insulates and supports axons [2].
What is different between the oligodendrocytes production of myelin and the Schwann cell production of myelin?
The primary difference is their location. Oligodendrocytes myelinate the central nervous system, while Schwann cells myelinate the peripheral nervous system. Oligodendrocytes are also capable of myelinating multiple axons, while Schwann cells can only myelinate one axon per cell.
How does myelination differ in the CNS and PNS quizlet?
Myelin protects and electrically insulates fibers. It also increases the transmission speed of nerve impulses. In the PNS, myelin sheaths are formed by Schwann cells. In the CNS, oligodendrocytes form the myelin sheath.
What is the difference between a myelinated and unmyelinated axon?
When we talk about myelinated neuron, this simply means that the axon is covered by myelin sheath. If we talk about unmyelinated neuron, this means the axon is not covered by this myelin sheath. This then means that the conduction of nerve impulse is slower.
What is the difference between the CNS and the PNS quizlet?
the CNS is the control center, brain and spinal cord. The PNS is nerve fibers that carry information to and from the CNS. White matter is myelinated fibers and is in the inside of the brain and outside of spinal cord. You just studied 85 terms!
What cells are responsible for myelination in the CNS and PNS?
Schwann cells make myelin in the peripheral nervous system (PNS: nerves) and oligodendrocytes in the central nervous system (CNS: brain and spinal cord). In the PNS, one Schwann cell forms a single myelin sheath (Figure 1A).
Which of the following are differences between oligodendrocytes and Schwann cells?
The key difference between oligodendrocytes and Schwann cells is that a single oligodendrocyte can extend up to 50 axons and form myelin sheaths which are 1 µm length in each axon while a single Schwann cell can wrap around only a single axon and form one myelin segment.
What does myelination by oligodendrocytes do?
Oligodendrocytes are the myelinating cells of the central nervous system (CNS). They are the end product of a cell lineage which has to undergo a complex and precisely timed program of proliferation, migration, differentiation, and myelination to finally produce the insulating sheath of axons.
How are axons and dendrites alike in what ways structurally and functionally do they differ?
Dendrites and axons are alike in that they both function to carry electrical current. Dendrites differ in that they are short, transmit toward the cell body, and function as receptor sites. Axons are typically long,myelinated, and transmit away from the cell body.
How does the CNS tell the difference between a weak stimulus and a strong one?
A strong stimuli constantly gives off a high frequency, leading to an intense reading of the stimuli. A weak stimuli provides a low frequency of action potentials, leading to a weaker reading of the stimuli.
How are PNS and CNS cells involved in myelination?
PNS and CNS myelination. During myelination, Schwann cells and oligodendrocytes, undergo dramatic morphological changes in order to generate their large specialized membrane extensions that warp axons in multiple layers. In the CNS for example, oligodendrocyte progenitors are settled along the fiber tracts that will be myelinated,…
What happens to Schwann cells during myelination?
During myelination, Schwann cells and oligodendrocytes, undergo dramatic morphological changes in order to generate their large specialized membrane extensions that warp axons in multiple layers.
How is myelin formed in the peripheral nervous system?
Myelin is formed by Schwann cells in the peripheral nervous system (PNS) and oligodendrocytes in the central nervous system (CNS). Each Schwann cell forms a single myelin sheath around an axon. In contrast, each oligodendrocyte forms multiple sheaths (up to 30 or more) around different axons ( Figure 1 ).
Where are myelinated axons located in the nervous system?
Here, we briefly describe the organization of myelin and of myelinated axons, as well as the functions of myelin in nerve conduction and neural circuits, and consider its potential evolutionary origins. Myelin is formed by Schwann cells in the peripheral nervous system (PNS) and oligodendrocytes in the central nervous system (CNS).