nervous system Flashcards
functions of nervous sys.
-responses to external/internal enviroment
-maintain homeostasis(tg with endocrine)
neuron
a nerve cell=communicates with other cells via specialized connections called synapses
neurotransmitters
-at most synapses
-chemical messengers
poytsynaptic cell
-the neuron,muscle or gland cell that recieves the signalg
glial cells=glia
supporting cells
sensory neuron
-transmit info about external(light,touch) or internal conditions(muscle tension, blood p.)
interneurons
responsible for analysis and interpretation of sensory input
motor neurons
-transmit signals to muscle cells,causing them to contract
-,additional neurons that extend out of the processing centers
presynaptic
transmitting neuron
properties of neuron
irritability -can be stimulated to make impulse
conductivity(dráždivosť)-able to transfer an impulse along the full length of their axons then on other muscles,neurons,glands
sponges
no true NS
diffuse nerve net
-cnidaria
-interconnected neurons control the expansion and contraction of gastrovascular activity
more complex animals
forming of nerves
bilateral symmetry
-key point in the evolution in NS
-cephalization(focus of the NS at the head end)
-centralization(the presnce of CNS from PNS)
CNS in vertebrates
-the brain,spinal cord
-brain combines gained info and coordinates all the activity of the body of bilateral animals(except jellyfish ,sponge)
spinal cord
-center canal filled with cerebrospinal fluid
-grey matter (butterfly )inside
-white matter outside
function of a spinal cord
-major reflex centre
-in charge of autonomos functions(sweating etc)
brain 5 parts
-medulla oblongata
-hindbrain(pons and cerebellum)
-diencephalon-thalamus,hypothalamus
-midbrain
-forebrain
medulla oblongata function
-contains the cardiac ,respiratory snd vasomotor(bp) cdenter
-responsible for autonomic involuntary actions
-in lower vertebrates(coordiination of movement
2 parts of hindbrain
-pons-connects the midbrain to medulla oblongata,controls bresthing
-cerebellum:
-learning and remembering motor response
-motor control and coordination
-conveys signal to cerebretal cortex
midbrain
-short
fish,amphibians:control of movement
mammals:centre of visual and auditory reflexes
keeping head in a good position ,FIGHT OR FLIGHT
Diencephalon thalamus
-thalamus-gateway to consciousness
-R,M,B:visuail ,auditorxy,sensory and painful stimuli,responsible for emotions
-F,A:most important part of the brain
funcitons of diencephalon hypothalamus
-homeostatic control centre
-controls bodx temperature
-bio clocl(cirkadianny)
-controls pituitary gland
forebrain
-the most developed part
-2 hemispheres divided by longitidual fissure,protected by cerebratal cortex
forebrain functions
fronter part responsible for motoric functions ,posterior partb for sensory functions
-MAJOR role in memory ,learning,speechn and emotion
-formulates complex behavioral responses
