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anatomy midterm 1
Question | Answer |
---|---|
factors that maintain a resting potential membrane potential | 1. unequal distribution of ions in the ECF and cytosol 2. inability of most anions to leave the cell 3. elecrogenic nature of Na/K ATPase |
sequence of events that generate an action potential | 1.depolarizing phase 2.repolarizing phase |
graded potential | small deviation from the resting membrane potential that make the membrane wither more polarized of less polarized |
where do graded potentials most offten occure | dendrites and cell body of neuron |
ionotropic receptor | ion channels that directly bind to the neurotransmitter |
metabotropic receptors | are G proteins that bind to the neurotransmitter but are not the ion channel. instead, the binding protein initiates ion flow through with in another protein |
2 classes or neurotransmitters | small-molecule neurtransmitter, neuropeptides |
three meninges | outermost-dura mater middle-arachnoid mater innermost- pia mater |
how many pairs of spinal nerves | 31, 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal |
posterior root | contains sensory nerve fibers and conduct nerve impulses from the periphery into the spinal cord; the posterior root ganglion contains the cell bodies of the sensory neurons from the periphery |
anterior root | contains motor neuron axons that conduct impulses from the spinal cord to the periphery; the cell bodies of motor neurons are located in the gray matter of the cord |
what does the gray matter primarily consist of | cell bodies of neurons and neuroglia and unmyelinated axons and dendrites of association and motor neurons |
what does the white matter primarily consist of | bundles of myelinated axons of motor and sensory neurons |
axon connective tissue sheaths | a fiber is a single axon with in an endoneurium, a fascicle is a bundle of fibers within a perineurium, a nerve is a bundle of fascicles within an epineurium |
five functional components of a reflex arc | receptor, sensory neuron, integrating center neuron, motor neuron, effector |
ipsilateral | same side |
what does the blood brain barrier do | protects brain cells from harmful substances and pathogens by serving as a selective barrier to prevent passage of many substances from the blood to the brain |
electrical synapse | ionic current spreads to next cell though gap junctions, faster, two-way transmition and capable of synchronizing groups of neurons |
chemical synapse | one-way information transfer from a presynaptic neuron to a postsynaptic neuron. |
nerve 1, name, classification, function | olfactory, sensory, smell |
nerve 2, name, classification, function | optic, sensory, vision |
nerve 3, name, classification, function | oculomotor, motor, eye movement and pupil dilation |
nerve 4, name, classification, function | trochlear, motor, eye movement |
nerve 5, name, classification, function | trigeminal, mixed, sensory-touch on face, corneal reflex, motor-muscles of mastication |
nerve 6, name, classification, function | abducens, motor, eye movement |
nerve 7, name, classification, function | facial, mixed, sensory-taste, motor-facial muscles, corneal reflex |
nerve 8, name, classification, function | vestibulocochlear, sensory, balance and hearing |
nerve 9, name, classification, function | glossopharyngeal, mixed, sensory-taste gag reflex, motor-elevates pharynx during speech |
nerve 10, name, classification, function | vagus, mixed, sensory-taste, motor-parasympathic to visceral organs, gag reflex |
nerve 11, name, classification, function | accessory, motor, muscles of neck and upper back |
nerve 12, name, classification, function | hypoglossal, motor, tongue movement |
what does CSF do? | absorbs shock and protects the brain and spinal cord, helps transport nutrients and wastes from the blood and nervous tissue |
what is the major secretory site for CSF | choriod plexus |
centers of the medulla oblongata | vital centers-cardiovascular and respiratory centers, other centers-vomiting, swollowing, sneezing, coughing, and hiccuping |
functions of cerebellum | anterior and posterior lobes coordinate movements, regulate posture; flocculonodular lobe coordinates balance |
parts of the midbrain | substantia nigra, red nucleus, reticular activating system |
substantia nigra | large area with dark pigments, help control subconscious muscle activities. loss of neurons here is associated with Parkinson's disease |
red nucleus | help control voluntary movements of the limbs |
reticular activating system (RAS) | consists of sensory axons that project to the cerebral cortex. helps maintain consciousness |
Thalamus | intermediate mass, contains several nuclei, major relay station for most sensory impulses, major relay for intracerebral and cerebro-cerebellar association |
hypothalamus | inferior to the thalamus, consists of mammillary body, median eminence, infundibulum, and a number of nuclei |
functions of hypothalamus | control of ANS (many viseromotor functions integration with other expressed behaviors) control release of pituitary hormones, regulation of emotional and behavioral patterns, eating and drinking, body temp. and circadia rhythms |
central sulcus | separates frontal and parietal lobes |
precentral gyrus | primary motor area |
postcentral gyrus | primary somatosensory area |
function of pons | relays nerve impulses related to voluntary skeletal movements from the cerebral cortex to the cerebellum |
function of midbrain | conveys motor impulses from the cerebrum to the cerebellum and spinal cord, sends sensory impulses from the spinal cord to the thalamus and regulates auditory and visual reflexes |
corpus collosum | a bundle of transverse white fibers where internal communication between hemispheres occurs |
function of basal ganglia | help initiate and terminate body movements |
functions of limbic system | functions in emotional aspects of behavior and memory, and is associated with pleasure and pain |
two main routes in spinal cord white matter sensory input travels | posterior column and the spinothalamic tract |
the three primary vesicles | proenchephalon, mesenchephalon, rhombencephalon |
the second brain vesicles | the proenchephalon develops into the telecephalon and diencephalon. the rhombencephalon develops into the metencephalon and the myelencephalon |
what parts of the brain to each of the 5 vesicles form | teleceohalon-cerebral hemisphere lateral ventricles. diencephalon-thalamus, hypothalamus, epithalamus third ventricle. mesencephalon-midbrain aqueduct. metencephalon-cerebellum upper 4th ventricle. myelencephalon-medulla oblongata, lower 4th ventricle |