Igneous Rocks Form from ________

question 17

Multiple Choice

Igneous rocks form from ________.

• A)heat and pressure applied to a rock
• B)precipitation of minerals out of a solution
• C)sediments cemented together
• D)molten rock cooling and forming crystals

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Definitions:

Axon

A thin, elongated extension of a neuron that usually transmits electrical signals from the neuron's cell body outward.

Dendrite

The branched projections of a neuron that act to conduct the electrochemical stimulation received from other neural cells to the body, or soma, of the neuron from which the dendrites project.

Myelin Sheath

An insulating layer around nerves, made of protein and fatty substances, which helps increase the speed at which electrical impulses propagate.

Node of Ranvier

Gaps in the myelin sheath along a nerve fiber, allowing for the rapid transmission of nerve impulses through saltatory conduction.