Functional Organization of Nervous Tissue

These flashcards cover essential vocabulary and concepts related to the functional organization of nervous tissue, including key terms, definitions, and their relevance in neuroscience.

Neurons

The communicating cells of the nervous system, utilizing electrical and chemical signals.

Glial cells

Supportive cells in nervous tissue that have many functions, including maintaining homeostasis and assisting neurons.

Ganglion

A collection of neuron cell bodies located outside the brain and spinal cord.

Plexus

An extensive network of axons and sometimes neuron cell bodies located outside the CNS.

Central Nervous System (CNS)

Consists of the brain and spinal cord.

Peripheral Nervous System (PNS)

Consists of sensory receptors and nerves that connect the CNS to the rest of the body.

Action potential

An electrical signal that is generated when a neuron reaches a threshold level of stimulation.

Resting membrane potential

The electrical potential across the plasma membrane of a resting neuron, typically around -70mV.

Depolarization

The process by which the inside of a neuron becomes more positive than its resting potential, typically due to sodium ion influx.

Hyperpolarization

The process by which the inside of a neuron becomes more negative than its resting potential.

Synapse

The junction between two neurons where action potentials can be transmitted from one neuron to another.

Neurotransmitter

Chemical messengers released by neurons that transmit signals across synapses.

Graded potential

A small change in the membrane potential that can summate and lead to an action potential when threshold is reached.

Myelin sheath

An insulating layer formed around the axons of many neurons, aiding in the speed of neural signal transmission.

Schwann cells

Glial cells in the PNS that wrap around axons to form the myelin sheath.

Oligodendrocytes

Glial cells in the CNS that produce myelin for axons.

Reflex arc

The neural pathway that mediates a reflex action.

Afferent neurons

Sensory neurons that carry signals towards the CNS.

Efferent neurons

Motor neurons that carry signals away from the CNS to effectors.