A _____ Is a Layer of Fat Cells That Encases

question 60

Multiple Choice

A _____ is a layer of fat cells that encases and insulates many axons and helps electrical signals travel faster down the axon.

• A) myelin sheath
• B) synapse
• C) dendrite
• D) placenta

---

Definitions:

Membrane Potential

The electric potential difference across a cell's plasma membrane, crucial for the transmission of nerve impulses and muscle contraction.

Local Potential

A reversible, localized change in the electrical potential of a neuron's membrane, which can lead to an action potential if a certain threshold is reached.

Depolarization

A reduction in the difference in electric charge across a cell membrane, which is essential for generating action potentials in neurons and muscle cells.

Repolarization

The process of restoring the negative charge inside the cell membrane after a depolarization event.