chapter 11-Nervous system Flashcards
dendrites
cytoplasmic extension that receive information and transmit it towards the cell body
soma
contains the nucleus and controls the metabolic activity of the neuron
axon
transmits AP away from the cell body
synaptic terminal
where the axon terminates
saltatory conduction
at the nodes of ranvier where the AP propagate
which cells produce myelin
glia cells ( oligodendrocytes ) in CNS and schwann cells in PNS
what is the resting potential
-70mV
what is the threshold potential
-55mV
what is the depolarization potation
+35mV
what channels open after depolarization and what happens
Na channels and Na come in
what channels open during repolarization and what happens
K channels K leaves
what is refractory period
hyperpolarization
- a period of time after the AP in which new AP are very difficult to initiate
what do things makes an AP travel faster
increased diameter of neuron and myelination
effector cells
cells other than neurons that neurons can communicate with
steps of NT release
1) AP arrives at axon terminal
2) depolarizes it
3) synaptic vesicles fuse with the presynaptic membrane and release NT into the synapse
4) NT diffuses across synapse and acton receptor proteins embedded i the postsynaptic membrane
5) release of NT=depolariztion of post synaptic cell and consequent firing of AP
neurons that carry sensory information about the external or internal environment to the brain or spinal cord are called
afferent neurones
neurons that carry motor commands from the brain or spinal cord to various parts of the body are called
efferent neurons
network of nerve fibres
plexus
neuronal cell bodies often cluster together into clusters called
ganglia
what cells support and protect specialized neuronal cells
neuroglia
what cell maintains the integrity of the blood-brain barrier, regulate nutrient and dissolved gas [ ], and absorb the recycle NT
astrocytes
-CNS
what cell myelinated CNS as well as provide structural framework for the CNS
oligodendrocytes
in the CNS which cell removes debris and pathogens
microglia
in the PNS which cells surround the neuron cell bodies in the ganglia
satellite cells
in the PNS which cells enclose the axons in the PNS and aid in the myelination of some peripheral axons
schewann cells
which cell in the CNS line the brain ventricles and aid in the production, circulation and monitoring of cerebral spinal fluid
Ependymal cells
what part of the part processes and integrates sensory inputted motor responses and is important for memory and creative thought
cerebral cortex
what part of the brain forebrain, midbrain or hindbrain consist of the telencephalon (cerebral cortex and olfactory bulb) and diencephalon ( thalamus and hypothalamus)
forebrain
what part of the brain forebrain, midbrain or hindbrain relay centre for visual and auditory impulses
midbrain
what part of the brain forebrain, midbrain or hindbrain consists of the cerebellum, the pons, and the medulla
hindbrain
what part of the brain is a relay and integration centre for the spinal cord and cerebral cortex
thalamus
what part of the brain controls visceral functions like hunger, thirst, sex drive, water balance blood pressure and temperature regulation
hypothalamus
what helps modulate motor impulses initiated by the cerebral cortex and is important in the maintenance of balance, hand-eye coordination and the timing of rapid movement
cerebellum
what part of the hindbrain is to act as a relay centre to allow the cortex to communicate with the cerebellum
pons
what part of the hindbrain is to control many vital functions such as breathing, heart rate and GI activity
medulla
what parts of the brain make up the brainstem
midbrain, pons, medulla
somatic nervous system
innervates skeletal muscle and is responsible for voluntary movement as well as reflex arcs (pathways that control motor reflexes)
autonomic nervous system
regulates the boys internal environment without the aid of conscious control
synaptic nervous system
flight or fight that ready the body for action in an emergency situation
sympathetic nervous system or parasympathetic nervous system: decrease bp, hr, increases blood flow to skeletal muscle, decrease gut motility, dilates the bronchioles to increases gas exchanges
sympathetic nervous system
parasympathetic nervous system
rest or digest
- conserve energy and restore the body to resting activity after exertion
what is the primary NT of the sympathetic nervous system
norepinephrine
sympathetic nervous system or parasympathetic nervous system: lower heart rate and increase gut motility
parasympathetic nervous system
what is a very important parasympathetic nerve that innervates many of the thoracic and abdominal viscera
vagus nerve
what is the primary NT of the parasympathetic nervous system
acetylcholine
thick opaque layer that covers the eyeball
sclera
what part of the eye helps to supply the retina with the blood
choroid
dark pigmented area that reduces reflection in the eye
choroid
what part of the eye bends and focuses light rays
cornea
what part of the eye responds to intensity of light in the surrounding
iris
what part of the eye focuses the image onto the retina
retina
what part of the eye helps maintain its shape and optical properties and is a jelly like material
vitreous humour
a water jelly like substance that fills the space between the lens and the cornea
aqueous humour
what photoreceptors respond to high-intensity illumination and are sensitive to colour
cones
what photoreceptors detect low-intensity illumination and are important in night vision
rods
what colour pigment wavelength do cones have?
red, green, blue
what is rhodopsin
rodes pigment
what is myopia
nearsightedness- occurs when the image is focused in front of the retina
what is hyperopia
farsightedness- occurs when the image is focused behind the retina
what is astigmatism
caused by an irregularly shaped cornea
what is cataracts
develop when the lens becomes opaque; light cannot enter the eye and blindness results
is an increase of pressure in the eye bc of blocking of the outflow of the aq humour which results in optic nerve damage
glaucoma
what is the visible part of the ear
pinna
what part of the ear focuses the sound wave toward the tympanic membrane
external auditory canal
what are the 3 bones in the middle ear
malleus (hammer), incus (anvil) and stapes ( stirrup) =ossicles
what part of the ear contains the cochlea and vestibules
oval window
