Nodes of Ranvier

The nodes of Ranvier are small gaps in the myelin sheath that covers the axons of neurons. These gaps are crucial for the rapid conduction of nerve impulses along the axon.

Structure

The nodes of Ranvier are regularly spaced interruptions in the myelin sheath that surrounds the axon. They are rich in voltage-gated sodium channels, which play a key role in the propagation of action potentials.

Function

During the propagation of a nerve impulse, the action potential "jumps" from one node of Ranvier to the next, a process known as saltatory conduction. This allows for faster conduction of the nerve impulse along the axon, conserving energy and speeding up transmission.

Study Guide

What are the nodes of Ranvier?
Describe the structure of the nodes of Ranvier.
Explain the function of the nodes of Ranvier in the conduction of nerve impulses.
How does saltatory conduction contribute to the efficiency of nerve impulse transmission?

◂Science Worksheets and Study Guides Eighth Grade. Fossils

Vocabulary/Answer key

Fossils

Vocabulary/Answer key

Fossils

The resources above cover the following skills:

Earth/Space Science: Students will use scientific skills and processes to explain the chemical and physical interactions (i.e., natural forces and cycles, transfer of energy) of the environment, Earth, and the universe that occur over time.

Earth History: Recognize and explain that fossils found in layers of sedimentary rock provide evidence of changing life forms.

Recognize how different types of fossils are formed, such as petrified remains, imprints, molds and casts.

Recognize and explain that the fossil record of plants and animals describes changes in life forms over time.