Nervous System Organization
This system imcludes the brain and spinal cord.
What is the central nervous system (CNS)?
Primary cells that carries signals.
What is a neuron?
Region that receives signals from other neurons
What are dendrites?
Normal resting membrane potential value
What is -70 mV?
Functional connection between a neuron and another cell
What is a synapse?
This system is outside the brain and spinal cord and connects to the body.
What is the peripheral nervous system (PSN)?
Cells that provide nutrients and structure ("nerve glue")
What are neuroglia cells?
The biosynthetic and receptive center of the neuron
What is the cell body (soma)?
Phase where membrane becomes less negative due to Na⁺ entering
What is depolarization?
Type of synapse that uses neurotransmitters
What is a chemical synapse?
This division carries signals to the CNS.
What is the sensory (afferent) division?
Neuroglial cells that wrap around axons for insulation in the PNS
What are Schwann cells?
Region where the action potential starts
What is the axon hillock?
Phase where K⁺ leaves and membrane becomes more negative
What is repolarization?
Ion that enters the axon terminal to trigger neurotransmitter release
What is calcium (Ca²⁺)?
This division carries signals away from the CNS to muscles/glands/
What is the motor (efferent) division?
Neuroglial cells responsible for myelination in the CNS
What are oligodendrocytes?
Three properties of neurons
What are excitability, conductivity, and secretion?
Phase where membrane potential goes below resting
What is hyperpolarization?
Process where neurotransmitter is taken back into the presynaptic neuron
What is reuptake?
This system controls voluntary movement like walking or raising your hand.
What is the somatic nervous system?
Cell type that removes dead/dying neurons (acts like macrophage)
What are microglia?
This must be reached for an action potential to occur
What is threshold?
Type of signal that is “all or none”
What is an action potential?
Three ways neurotransmitter effects are terminated
What are reuptake, enzymatic degradation, and diffusion away?