Nervous System and Parts of a Neuron

Central Nervous System (CNS)

Brain and spinal cord, “command center,” processes and stores sensory information

Peripheral Nervous System (PNS)

Every nerve outside brain and spine, connects CNS to rest of body, carries info in and out (split into 2 other systems [Somatic and Automatic])

Somatic Nervous System

Controls voluntary skeletal muscles, the movement of your body

Automatic Nervous system

Controls glands and internal organs automatically, things like digestion, heartbeat, etc (also has two subsystems [sympathetic and parasympathetic])

Sympathetic Nervous system

“fight-or-flight response, heart rate up, pupils dilate, arousal system

Parasympathetic Nervous system

“rest and digest,” returns body back to baseline, calming system

Dendrites

Tree-like extensions that receive incoming signals from other neurons and carry them towards soma

Soma (cell body)

Contains the nucleus, acts as control center and keeps neuron alive

Axon

Long fiber extending from cell body, takes signals (action potential) away from cell body to other neurons

Myelin Sheath

Layer wrapped around the axon that speeds up the process of the electrical signal down the axon

Axon Terminals

End branches of the axon, releasing neurotransmitters across the synaptic gap to communicate with the next target

Neurotransmitter

Messenger released into synaptic gap, binding to receptor sites on receiving neuron

Reuptake

The sending neuron reabsorbs leftover neurotransmitter

Agonist

Substance that mimics or boosts a neurotransmitters effect

Antagonist

Substance that blocks a neurotransmitters effects