How an axon in the peripheral nervous system becomes myelinated?

Myelin is formed in the PNS (peripheral nervous system) and CNS by the innermost sheet-like glial process in contact with the axon spiraling around it and spinning out multiple layers of overlapping membrane . Cytoplasm becomes expelled from all but the innermost and outermost layers of the myelin sheath.

What divisions of the nervous system that involuntarily control smooth muscle cardiac muscle and glands?

The autonomic nervous system is the part of the nervous system concerned with the innervation of involuntary structures, such as the heart, smooth muscle, and glands within the body.

How does an axon in the PNS become myelinated?

Answer and Explanation: The axons of the peripheral nervous system are myelinated by Schwann cells wrapping their membrane around it . In the peripheral nervous system, Schwann cells are the glial cells repsonsible for myelination. The Schwann cell extends its cell membrane and wraps it around one axon of one neuron.

What is the process of myelination in the PNS?

In the PNS, myelination is preceded by invasion of the nerve bundle by Schwann cells, rapid multiplication of these cells and segregation of the individual axons by Schwann cell processes .

Which part of the peripheral nervous system controls smooth muscle cardiac muscle and glands?

The autonomic nervous system , also called the visceral efferent nervous system, supplies motor impulses to cardiac muscle, to smooth muscle, and to glandular epithelium.

What component of PNS is responsible in the control of smooth and cardiac muscles?

The autonomic nervous system (ANS) is the component of the peripheral nervous system that controls cardiac muscle contraction, visceral activities, and glandular functions of the body.

What division of the PNS regulates the activity of cardiac and smooth muscles organs and glands?

The autonomic nervous system is a component of the peripheral nervous system that regulates involuntary physiologic processes including heart rate, blood pressure, respiration, digestion, and sexual arousal. It contains three anatomically distinct divisions: sympathetic, parasympathetic, and enteric.

How does myelination of axons occur in the PNS?

Within the peripheral nervous system the process of myelination begins with a Schwann cells wrapping around a portion of the axon of a neuron . Multiple layers of myelination are formed as the Schwann cells wraps itself in consecutive layers around the axon.

How is the formation of myelin in the peripheral nervous system?

Peripheral nervous system (PNS) myelin is formed by the differentiation of the plasma membrane of Schwann cells . One of the biochemical characteristics that distinguishes myelin from other biological membranes is its high lipid-to-protein ratio.

How does a peripheral neuron axon regenerate?

After an injury to the axon, peripheral neurons activate a variety of signaling pathways which turn on pro-growth genes, leading to reformation of a functional growth cone and regeneration . The growth of these axons is also governed by chemotactic factors secreted from Schwann cells.

Are peripheral nerves myelinated?

In peripheral nerves, Schwann cells form myelin , which facilitates the rapid conduction of action potentials along axons in the vertebrate nervous system. Myelinating Schwann cells are derived from neural crest progenitors in a step-wise process that is regulated by extracellular signals and transcription factors.

Art-labeling Activity: Parts of a Myelinated Peripheral Nervous System (PNS) NeuronDrag the labels onto the diagram to identify the parts of a myelinated PNS neuronReset HelpAxon hillockNucleusNodesInitial Segment (unmyelinated)Myelinated internode (2024)

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Art-labeling Activity: Parts of a Myelinated Peripheral Nervous System (PNS) Neuron Drag the labels onto the diagram to identify the parts of a myelinated PNS neuron Reset Help Axon hillock Nucleus Nodes Initial Segment (unmyelinated) Myelinated internode (2024)

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