5 The Nervous System Free Online FlashCards

What is a neuron?

A neuron is a cell specialized for communication.

What do dendrites do?

Dendrites receive many incoming signals.

How does an axon often communicate across a synapse?

A synapse is a junction where an axon communicates with another cell, often by releasing chemical messengers called neurotransmitters.

What does myelin do?

Myelin is an insulating covering around some axons that helps signals travel quickly.

How do oligodendrocytes and Schwann cells differ in myelination?

Oligodendrocytes form myelin in the CNS and can myelinate portions of multiple axons. Schwann cells form myelin in the PNS, typically around one segment of one axon.

What do astrocytes do in the CNS?

Astrocytes help regulate the chemical environment around neurons in the CNS.

What structures make up the CNS?

The CNS consists of the brain and spinal cord; it integrates information and helps select responses.

What is the role of the PNS?

The PNS includes nerves and ganglia outside the brain and spinal cord and carries signals between the CNS and the rest of the body.

What is a ganglion?

A ganglion is a cluster of neuron cell bodies in the PNS.

Which way do sensory, or afferent, pathways carry information?

Sensory, or afferent, pathways carry information from receptors toward the CNS.

How do somatic and autonomic motor systems differ?

The somatic motor system controls skeletal muscle; the autonomic motor system regulates smooth muscle, cardiac muscle, and glands, generally without conscious control.

What are the three stages of a basic sensory and motor pathway?

A basic pathway has three stages: reception of a stimulus, integration of information in the CNS, and a response by an effector.