Myelinated vs Non-Myelinated Nerve Fibers

The video tutorial discusses the differences between myelinated and non-myelinated nerve fibers. Myelinated fibers, also known as white or medullated fibers, have a myelin sheath and are found in the brain, spinal cord, and peripheral nerves. They feature nodes of Ranvier and are covered by a neurilemma. Non-myelinated fibers, or gray fibers, lack a myelin sheath and are found in autonomic ganglia. The tutorial explains the structure and function of these fibers, highlighting the presence of Schwann cells and the absence of myelin in non-myelinated fibers.

What is another name for myelinated nerve fibers?

• White nerve fibers

• Autonomic ganglia fibers

• Gray nerve fibers

• Non-medullated fibers

Where are myelinated nerve fibers primarily found?

• In the muscles

• In the skin

• In the brain and spinal cord

• In the digestive system

What is the function of the myelin sheath?

• To connect neurons together

• To protect the axon

• To provide nutrients to the axon

• To insulate the axon and speed up nerve impulses

What are the interruptions in the myelin sheath called?

• Internodes

• Myelin clefts

• Cementing discs

• Nodes of Ranvier

What is the distance between two nodes of Ranvier called?

• Node distance

• Internode

• Axonal gap

• Myelin space

What is absent in non-myelinated nerve fibers?

• Nucleus

• Axon

• Myelin sheath

• Cytoplasm

Which type of nerve fibers are found in autonomic ganglia?

• Myelinated fibers

• Medullated fibers

• White nerve fibers

• Non-myelinated fibers

What surrounds the axon in non-myelinated nerve fibers?

• Cementing disc

• Myelin sheath

• Nodes of Ranvier

• Cynthial sheath of Schwann cells

Which of the following is a characteristic of myelinated nerve fibers?

• They have a continuous myelin sheath

• They lack a myelin sheath

• They have nodes of Ranvier

• They are found in autonomic ganglia

What is a key difference between myelinated and non-myelinated nerve fibers?

• Presence of axons

• Presence of myelin sheath

• Function in the nervous system

• Location in the body