Test 2 Flashcards
Nervous system
The body’s system that handles processing info, sending electrochemical signals throughout the body using billions of neurons. It regulates the communication of information
Peripheral nervous system
nerves that connect the central nervous system to organs and muscles
Somatic nervous system
in charge of voluntary actions, it passes commands from CNS to skeletal muscle. As well as conveying sensory information to the CNS.
Autonomic nervous system
in charge of involuntary actions and passes CNS commands to blood vessels, internal organs and glands
Sympathetic system
fight or flight response, used when there is a conflict or threat
Parasympathetic system
rest or digest response, conserves energy and helps with digestion
Spinal cord
relays information between the brain and the PNS and controls spinal reflexes
Spinal reflexes
motor movements made without consulting the brain
Glial cells
helper cells; dispose of dead neurons, feed them, and are in charge of protection. Their insulation is myelin
Neuron
specialized nerve cells that receive and transmit info. Made of; cell body, dendrites, and an axon
Nucleus
contains chromosomes with our DNA
Cell body (Soma)
cell body that keeps the neuron alive. It synthesizes neurotransmitters and coordinates information
Dendrites
branch off soma and pass info to it, receives info from other neurons. It is covered in synapse receptors
Axon
elongated fiber off soma, conducting info from it to neurons, muscles, glands. The neural impulse goes in a one way direction in neuron
Myelin sheath
insulation around some axons, which speeds up signal travel. Made up by glial cells
Axon terminal
knob like endings, end at synapses. Contain vesicles with neurotransmitters that carry info to other neurons/cells
Action potential
an electric signal that sends info along the axon. Only triggered if total strength of all incoming signals from dendrites exceeds a firing threshold (all-or-none)
Demyelinating disease
When the myelin sheath is damaged; neural signals are slowed and distorted, axon deteriorates/is lost, neurological problems arise and movement, sensations, cognitions, internal organs are all impacted.
Synapse
Microscopic junction between axon terminals of the sending neuron and dendrites or soma of the receiving neuron. Transmission of signal between neurons
Neurotransmitters
A chemical messenger that carries the signal across the synaptic gap, to a receiving neuron’s dendrites. Excitatory action boosts the signal, inhibitory does the opposite
Endorphin
Natural pain killer-has a calm drowsy effect
Dopamine
regulates voluntary movement, attention/working memory and motivation
Norepinephrine
involved in fight or flight response. Talks to ANS
Serotonin
stabilizes our mood (well-being) and is important with sleeping and eating