communicates between different areas of organism, controls functions of the organism, regulates responses to conditions or sensory stimuli
1 of 30
Nerve cells
excitable cells capable of producing and transmitting electrical impulses termed action potentials
2 of 30
Action potential
transient change in the potential difference across the membrane of the neuron, flows down neuron, form basis of communication
3 of 30
Soma
neuronal cell body, contains nucleus, site of protein synthesis
4 of 30
Dendrites
many per neuron, receive incoming inputs from other neurons, converge in the soma
5 of 30
Axon
carries impulse to next neuron in series, axon terminal branches, insulated with fatty coating (myelin sheath)
6 of 30
Synapse
connection between axon terminal of one cell and dendrite of another cell, single axons connect to many dendrites, soma helps integrate inputs, huge number of synapses per neuron
7 of 30
How do synapses communicate?
action potential travels down presynpatic cell, stimulates response of neurotransmitter across synapse, neurotransmitter binds to receptors on postsynaptic cell, triggers action potential, impulse continues along cell
8 of 30
Neurotransmitters
can be returned to axon terminals for reuse, transported into glial cells, inactivated by enzymes or can diffuse out of synaptic cleft
9 of 30
Divergence
synpases expand signals down a certain nerve/tract divison
10 of 30
Convergence
synapses channel signals down a certain nerve/tract division
11 of 30
Afferent (incoming) neurons
carry information from periphery into nervous system, convert sensory information into action potentials using a variety of specialised receptors
12 of 30
Efferenct (outgoing) neurons
carry commands from nervous system to effectors
13 of 30
Interneurons (circuit/relay)
form connections between neurons, often afferent to efferent, increase nervous system complexity, store information
14 of 30
Neuron in retina
fewer dendrites, fewer inputs, deals with vision
15 of 30
Neuron in cerebellum
lots of dendrites, more inputs, controls intricate, complex movement
16 of 30
Neuron in cortex
branched dendrites, long axon, wide, long distance communication
17 of 30
Withdrawal reflex
simplest reflex, involves one afferent, one efferent and one interneuron, impulses travel to spinal cord, facilitates rapid response
18 of 30
Neuronal networks
arrangements containing more than one nerve cell, vary in complexity
19 of 30
Nerve net
simplest network, small numbers of connected neurons
20 of 30
Nervous system
complex network, huge number of cells connected, many components
21 of 30
Ganglia
paired or grouped neurons
22 of 30
Brain
main processing headquarters, 2 hemispheres, largest pair of ganglia
23 of 30
Spinal cord
thickened cluster of nerve fibres, connects parts of organism
24 of 30
Anemone
simple nerve nets, lengthy projections, few connections, permits simple responses, reflexes and functions
25 of 30
Earthworm
ganglia co-ordinate movement, anterior ganglia acts as control centre, co-ordinate more complex behaviour
26 of 30
Squid
greater degree of integration, specialised ganglia control specific functions, stellate ganglia/nerve co-ordinate intricate movement, vision co-ordinated by large visual ganglia
27 of 30
Human
most complex, huge number of nerve cells, ganglia and processing centres
28 of 30
Central nervous system
brain and spinal cord, processing centre encased in bone
29 of 30
Peripheral nervous system
information relay, communication system
30 of 30
Other cards in this set
Card 2
Front
excitable cells capable of producing and transmitting electrical impulses termed action potentials
Back
Nerve cells
Card 3
Front
transient change in the potential difference across the membrane of the neuron, flows down neuron, form basis of communication
Back
Card 4
Front
neuronal cell body, contains nucleus, site of protein synthesis
Back
Card 5
Front
many per neuron, receive incoming inputs from other neurons, converge in the soma
Comments
No comments have yet been made