Nervous System Flashcards
What does the nervous system do? what is it made up of?
made up of highly specialized cells; produce and conduct electrical messages (nerve impulses)
connects individual with their internal and external world
What is the function of a neuron?
transmits neural impulses to muscle, glands and other neurons
what are the three types of neuron?
sensory
motor
interneuron
Interneuron
takes a bipolar structure.
receives signals from sensory neurons and sends impulses to other interneurons or motor neurons.
Only found in brain, eyes, spinal cord
Sensory neuron
takes a unipolar structure
transmits impulses from receptors to the nervous sytsem
Motor neurons
takes a multipolar structure
carry outgoing signals for movement
what are the components of the neuron?
cell body/soma dendrites axon myelin synaptic terminals synapse
what is the soma?
Large egg shaped structure, provides fuel, manufacture chemicals, maintains
what are dendrites?
Project from the cell body in branch structure
receive neural impulses from adjacent neurons
what is an axon?
Slender tube that extends from the soma
transmits messages to other neurons
can be meters long
can be myelin coated to speed up transmission
what are myelin coated neurons
neurons that have fat coated axons peripheral nerves (sensory and motor)
What is a synaptic terminal?
small swellings at the end of the branched axon
what is a synapse?
the gap from one neuron to another
what are nerves?
a bundle of elongated axons belonging to thousands of neurons
what is a ganglion?
cell bodies outside of the brain and spinal cord
what is a nucleus?
cell bodies of the brain and spinal cord
what is Action potential
information that travel along neuron activating sodium and potassium channels allowing movement of ions in and out
what are ion channels?
chemical gates on the axon membrane that open to allow electronically charged particles to enter
what are ion pumps?
protein structures that maintain even distribution of ions across the cell.
positive on outside
negative on inside
what are neurotransmitters
more than 70 different chemicals produces by neurons that have different effect on different receptors. primary way messages are transmitted throughout NS
what effects can exercise have on the nervous system?
can effect sleep, mood, pain perception
what is the central nervous system?
Made up of the brain, brainstem and spinal cord
command post of the body
senses, processes, stores and responds to info
regulates and integrates bodily functions
what does the spinal cord do?
receives and transmits neurons from the brain to the periphery and vice versa
Afferent signals travel via dorsal horn
efferent signals travel via ventral horn
What is an efferent signal?
what is an afferent signal
efferent= motor afferent= sensory
what is the brainstem?
located at the top of spinal column
regulates life support systems, effects behavior and mood
consists of medulla, pons, midbrain
what is the peripheral nervous system?
all neurons outside of CNS
nerves that extend from spinal cord
carry messages to and from muscle glandes and sensory organs.
consists of: somatic, autonomatic
what is the somatic part of the PNS?
regulates voluntary movement of skeletal muscles
nerves contain afferent and efferent signals that connect to sensory receptors and muscles
what is the autonomic system?
Controls survival functions, involuntary muscles
contains sympathetic NS
Parasympathetic NS
eletronic NS
what is the sympathetic system
Involved in arousal and energy expenditure
triggered by threats
increases: HR, blood flow, blood sugar, adrenaline, slows digestion
What is the parasympathetic system?
Reverses sympathetic effects
maintains the body to a calmer state
conserves energy regulates elimination of waste products
slows HR, stimulates digestion
What is central fatigue?
A form of impairment that effects the NS
brain becomes unable to send enough signals impairing performance
what causes central fatigue?
the brain overheating
what is the process of heat entering or leaving the brain?
Cerebral perfusion
