Neuroscience (2b) Flashcards
Neruon
Nerve cell. It is the fundamental building block of the nervous system. Communication between neruons is vital for normal brain and spinal cord functioning
Sensory neuron
Gathers sensory information
Motor neuron
Communicates information to the muscles
Interneuron
Communicates with sensory and motor neurons and other inter neurons
Dendrites
Recive information from other neurons on and sensory receptors
Cell body
Receives information from the dendrites and if enough stimulation is received the message is passed onto the axon
Axon
Carries the neurons message to terminal buttons
Myelin sheath
Is a type of glial cell that covers segments o the axon to insulate and speed the neural impulses
Terminal buttons
Terminal buttons Of axon form junctions with other cells and reuse chemicals called neurotransmitters
Glia
Cells that make up the nervous system in addition to neurons
Astroglia
Creates blood-brain barrier, influences communication between neruons and helps heal brain damage
Oligodendroglia
Provides mylein to speed up transmission of neurons
Microglia
Cleans up dead cells and prevents infection in the brain
Resting potentional
When the neuron is at rest it is negatively charged (intercellular) relative to the outside (extracellular)
Action potential
When a neuron fires ion channels opens to let charged ions flor into and out of the neuron.
- the neuron becomes more positive in the inside relative to the outside
- the shift in electrical charge triggers axon terminals to release neurotransmitters
Refractory peroid
Immediately after a neuron is fired it cannot fire again - has to come back to resting.
All or nothing principle
Either a bro is sufficiently stimulated to start an action potential (all) or it is not (none)
Nodes of ranvier
Are the regions of bare axon that are between areas wrapped in myleyn. Action potentionals trave down yelled axons by jumping from node to node
Postsynaptic molecules
Are electrical events in post synaptic neurons that occur when a neurons transmitter binds to one of its receptors. When a receptor is activated, postive or negative ions can flow through the receptor into the neuron
Excitatory post synaptic potentials
Depolarize the neuron and increase the likelihood of an action potential
Inhibitory postsynaptic potentials
Hyper polarize the neuron and decrease the likelihood of an action potential
Neural network
Neruons form circuits or networks that expand the communication amoung different brain regions
Neuroplacicity
The brains ability to make new neural connections or to reorganize in response to injury or experience
