Nervous System Flashcards (cells + neuron structure & function)

What are the two main types of nervous system cells?

Neurons (signals cells) & neuroglia (support cells)

What is the main function of neurons?

Transmit electrical signals (nerve impulses)

What is the main function of neuroglia?

Support, protect, and nourish neurons

What are astrocytes?

Star-shaped glial cells that support neurons

Function of astrocytes?

Maintain blood-brain barrier & provide nutrients

What are oligodendrocytes?

Glial cells that form myelin in the CNS

Function of oligodendrocytes?

Insulates axons to speed up signals

What are microglia?

Immune defense cells in the CNS

Function of microglia?

Remove waste, pathogens, and damaged cells

What are ependymal cells?

Cells lining brain ventricles

Function of ependymal cells?

Produce & circulate cerebrospinal fluid (CSF)

What are Schwann cells?

Glial cells that form myelin in the PNS

What is the function of Schwann cells?

Speed up nerve signal conduction in peripheral nerves

What are satellite cells?

Support cells in the PNS around neuron cell bodies

Function of satellite cells?

Regulate environment around neurons

What are the three main parts of a neuron?

Dendrites, cell body (soma), axon

Function of dendrites?

Receive incoming signals

Function of the cell body (soma)?

Processes information & contains nucleus

Function of the axon?

Sends signals away from the neuron

What is the axon terminal?

End of axon that releases neurotransmitters

What is the synapse?

Gap between neurons where signals pass

What are neurotransmitters?

Chemicals that transmit signals across synapses

What is a nerve impulse?

Electrical signal traveling along a neuron

What is the resting potential?

Neurons stable charge when not firing (-70 mV)

What is an action potential?

Rapid electrical change that sends a signal

What is depolarization?

Inside of neuron becomes more positive

What is repolarization?

Neuron returns to negative resting state

What is the role of myelin sheath?

Speeds up impulse conduction

What are Nodes of Ranvier?

Gaps in myelin where impulses “jump”

What is saltatory conduction?

Jumping of impulses node to node (faster signaling)