Unit 7 Study Review Flashcards
What two systems can the nervous system be divided into?
Central nervous system and Peripheral nervous system.
Central contain brain and spinal cord.
Peripheral nervous system contains sensory and motor divisions.
Sensory division is divided into ____ and ____ sensory division.
Visceral sensory and Somatic sensory.
Motor division is divided into ___ and ____ division.
Visceral motor and somatic motor.
Visceral motor division is divided into ______ and ____ division.
Sympathetic and parasympathetic division.
What are the two inputs to sensory nervous systems?
Somatic sensory(eyes) and visceral sensory(blood vessels).
What are the two outputs of the motor nervous system?
Somatic motor(skeletal muscle) and automatic motor(cardiac muscle).
The cell in the nervous system is called _____.
Neuron.
Function of the neuron?
Generating electrical signals and releasing neurotransmitters.
What are the cells that are responsible for supporting neurons?
Glial cells.
What are the fingers that surround the neuron’s head? Function?
Dendrites. Area where they receive inputs from other neurons and form neuron networks.
What is the small area between the cell body and axon?
Axon hillock.
Where does the output start and end?
Axon hillock to axon terminals.
Where do the axon terminals attach to another neuron?
Dendrites.
What is the neural impulse?
Electrical signal traveling down the axon.
What is the myelin sheath?
Covers the axon of some neurons and helps speed neural impulses.
What are the four segments of a neuron?
Receptive segment, Initial segment, Conductive segment and Transmissive segment.
Where are the areas of each segment?
Receptive-Cell body and dendrites, Initial-Axon hillock, Conductive-Axon and Transmissive-Axon terminals.
What are the functions of each segment?
Receptive-productions of graded potentials/bind neurotransmitters.
Initial-summation of graded potentials and initiation of action potentials.
Conducive-propagation of action potential.
Transmission-action potential causes release of neurotransmitters.
What is the difference between presynaptic and postsynaptic neurons?
Before synapse and after synapse.
When the axon terminal innervates to dendrites or to another cell body, what is it called?
Synapse.
What are the four types of neurons?
Multipolar, bipolar, unipolar and anaxonic neuron.
What type of neuron is most motor and some interneuron? Explain what it looks like?
Multipolar neuron, it has dendrites connected directly to the cell body and one long axon with many axon terminals.
What is the special sense neuron that is uncommon and found in the olfactory? Explain what it looks like?
Bipolar neuron, two processes extend from the cell body of one dendrite and one axon.
What type of neuron is most types of sensory neurons? Explain what it looks like?
Unipolar, single short process that extends directly from the cell body. Looks like a T.
What are the three classifications of the function class of neurons?
(input)Sensory: five senses. (output)Motor: Innervates skeletal muscle. Interneuron: Connects neuron to neuron.
What are the 6 types of glial cells?
Astrocyte, microglia, ependymal, oligodendrocyte, satellite cells and schwann cells.
What are the functions of the 6 types of glial cells?
Astrocyte-forms blood brain barrier, microglia-kill bacteria/defends cells, ependymal-cover ventricle and whole CNS/produces CSF(liquid between cell and cell),
oligodendrocyte-covers the axon in CNS/produces myelin,
satellite cells-supporters of ganglia cells/covers cell body
schwann cells-same job as oligodendrocyte(forms myelin sheath) in PNS.
What is the space between each myelinated axon?
Node of ranvier.
What jumpers between nodes of ranvier?
Action potential.
What is the action potential jump between nodes of ranvier?
Saltatory conduction.
How does myelin sheath grow on the PNS axons by schwann cells?
Layers will be built over under each other and continuously overlap.
The surrounding connective tissue of the outer layer of a single axon is called _____.
Endoneurium.
The collection of bundled axons is called ___.
Fascicle.
The collection of multiple bundles of axons(fascicles) is called _____.
Nerve.
The nerve is surrounded by _____.
Epineurium.
The connective tissue between each fascicle/cover the fascicle is called ____.
Perineurium.
What is the cluster of cell bodies in the PNS(peripheral nervous system)?
Ganglia.
What is the cluster of cell bodies in the CNS?
Nucleus.
A nerve is?
Group of axons in PNS.
A tract is?
Group of axons in the CNS.
Gray matter is made of?
Cell bodies, dendrites, synapse and unmyelinated axons.
White matter is made out of?
Myelinated axon.
__ percent of the brain is made out of fat.
70%
What are the two pumps in neurons?
Ca2+ pump and Na+/K+ pumps.
What are the two leak channels?
K+ and Cl- leak channels.
What does the leak and pump channels cause?
Electrical gradient of the cell.
What are the three chemically graded channels?
Na+, K+ and Cl- channels.
What are the three voltage gated channels?
Na+, K+ and Ca2+ channels.
The dendrites contain what two chemically gated channels?
Na+ and Cl- chemically gated channels.
The two gated channels in the dendrites are opened by?
Neurotransmitters of other axon terminals.
When the sodium chemically gated channels open and the body cell becomes positive creating a potential it is called?
Excitatory postsynaptic potential(EPSP).
The axon contains what channels?
Voltage gated K+ and Na+ channels.
What is the resting membrane potential?
70 mV
When the voltage gated channels open on the axon hillock and whole axon what happens?
Action potential.
What voltage gated channels open on the axon terminal?
Voltage gated Ca2+(neurotransmitters).
When the voltage gated Ca2+ opens in the axon terminal what happens?
Ca2+ will cause induced exocytosis, where neurotransmitters will be released.
___ leak channels mainly contribute to resting membrane potential.
K+(and K+/Na+ pump restores the balance to resting potential).
Definition of voltage?
Difference in electrical charge across plasma membranes.
Definition of Current?
Movement of ions across membranes.
Definition of resistance?
Opposition to movement of ions, plasma membrane resitis ion movement. Resistance changes when ion channels open or close.
What is chemical synapse? Example?
Where neurotransmitters are released(12 total). Ligand gated ion channel or Na+.
What is an excitatory synapse?
A ligand gated channel of Na+ causes depolarization aka makes the inside more positive(EPSP).
What is an inhibitory synapse?
A ligand gated ion channel of Cl- causes hyperpolarization aka makes the inside more negative.
What are graded potentials?
Short lived changes in resting membrane potential.
Na+ causes _____ and Cl- causes _____.
EPSP(depolarization/peak of highest peak of membrane potential only) and IPSP(hyperpolarization/lowest dip of membrane potential only) before it will return to resting membrane potential(-70mV)
What are the two postsynaptic potentials?
EPSP(excitatory depolarization) and IPSP(inhibitory hyperpolarization).
What is summation?
Additive effects of EPSP and IPSP on membrane potentials.
What is spatial summation?
Multiple presynaptic neurons release neurotransmitters at the same time.
What is temporal summation?
One presynaptic neuron releases a neurotransmitter several times within a few milliseconds.
What is a subthreshold stimulus?
Not enough to generate AP at axon hillock.
What is the threshold stimulus?
Enough to generate AP at axon hillock.
How does hyperpolarization occur?
When voltage after K+ channels stay open longer than the time needed to reach the resting membrane potential, makes it becomes below -70mV.
How many stages are there in creating AP?
- 1 is resting, 2 is initial segment, 3 is depolarization, 4 is repolarization, 5 is hyperpolarization, 6 is voltage gated K+ are closed and returned to resting potential.
What is the absolute refractory period?
Time during AP when a second AP cannot be generated(between steps 2 and 4).
What is the relative refractory period?
Time during a second AP can be generated with sufficient stimulus(4 to 5).
What is continuous conduction?
Unmyelinated axons.
What is saltatory conduction?
Myelinated axons(node of ranvier), action potential jumps between nodes. It makes it much faster so all motor neurons use it.
What are the chemical structures of neurotransmitters?
Acetylcholine, biogenic amines, amino acids and neuropeptides.
What are the two categories of function for neurotransmitters?
Effects and actions.
What are the two types of neurotransmitters under effects?
Excitatory and inhibitory.
What are the two types of neurotransmitters under actions?
Direct(opens ion channels) and Indirect(cause response through activation of G proteins).
What are the four types of neurotransmitters?
Ach, Glutamate, norepinephrine(NE) and gamma-aminobutyric acid(GABA).
ACh is used in the motor neuron and autonomic nervous, central nervous system, and can be both excitatory and inhibitory.
Glutamate is a major excitatory neurotransmitter in CNS, linked to memory and learning.
Norepinephrine is excitatory and inhibitory, found in CNS for mood motivation and alertness(sympathetic). NE transporter for reuptake(recycled).
Gamma- aminobutyric acid is the primary inhibitory neurotransmitter in the brain(mainly binds with ligand gated Cl- ion channels). Reuptake into axon terminal and glial cells by GABA transporter. It is a tranquilizer.
Central nervous system has ____ and ___.
Brain and spinal cord.
Peripheral nervous system contains ___ and ___.
Cranial nerves and spinal nerves.
Cerebral cortex are?
Folds of brian tissue, with elevated ridges.
Sulcus is?
Shallow grooves that separate gyri(cerebral cortex).
Fissures are?
Deep grooves.
What are the two parts of gray matter?
Cerebral cortex and cerebral nuclei.
What is the cerebral cortex?
Gray matter surface of cerebrum/
What are the cerebral nuclei?
Are regions of gray matter(clusters of cell bodies) found deep into the cerebrum.
What are the three parts to white matter?
Inner white matter, corpus callosum and internal capsule.
What are the 4 functions of cranial meninges?
Three connective tissue layers separate and support soft tissue of the brain, enclose and protect blood vessels supplying the brain, help contain and circulate cerebrospinal fluid.
What are the three layers of cranial meninges?
Pia(touch the brain/softest), arachnode(between) and dura(hardest layer).
What is the pia mater?
Innermost if the meninges; adheres to the brain surface. Thin layer of connective tissue.
What is arachnoid mater?
Lies external to pia mater made from collagen and elastic fibers. Has two spaces.
What is dura mater?
Tough outer membrane made from irregular connective tissue in 2 layers, meningeal and periosteal.
The potential space between dura and skull that contains arteries and veins is called?
Ependymal space.
Ventricles are the ____?
Cavities within the brain, lined with ependymal cells(cerebrospinal fluid), contain 4 ventricles. Connect with each and with the spinal cord’s central canal.
What are the 4 ventricles?
Two lateral ventricles, third ventricle and fourth ventricle.
What are the two lateral ventricles?
Large cavities in cerebrum separated by medial partition and septum pellucidum.
What is the third ventricle?
Narrow space in the middle of diencephalon, connected to each lateral ventricle by an interventricular foramen.
What is the fourth ventricle?
Sickle shaped space between pons and cerebellum. Connected to the third ventricle by cerebral aqueduct. Opens to subarachnoid space medially and laterally. Narrows before merging with the central canal of the spinal cord.
What is cerebrospinal fluid(CSF)?
Clear colorless liquid surrounding CNS. Circulates in ventricles and subarachnoid space, protects CNS by providing cushion. Keeps the CNS environment stable.
CSF is formed by?
Choroid plexus, a special tissue inside the ventricle.
CSF contains more Na+ and Cl-.
Blood plasma is filtered through capillary and midfield by ___.
Ependymal cells.
What is CSF circulation?
Where CSF is continuously formed and reabsorbed.
What are the 5 steps to CSF circulation?
Formation in choroid plexus, flows from lateral ventricles into third ventricle, then into fourth ventricle, flows into central and canal of spinal cord, excess CSF flows into arachnoid villi and drains into dural venous sinuses.
What are the four main parts of the brain?
Cerebrum, diencephalon, cerebellum and brainstem.
What are the 3 areas under the brainstem?
Midbrain, pons, medulla oblongata.
What is the deep cleft that separates the right and left hemispheres?
Longitudinal fissure.
What is the largest tract that provides connection between the right and left hemispheres?
Corpus callosum.
What is lateralization?
When higher functions are controlled by one side of the brain.
What are the four lobes?
Frontal parietal, occipital and temporal lobes.
What is in between temporal and frontal lobes?
Gyri of insula.
What are the functions of the frontal lobe?
Primarily motor cortex, premotor cortex, frontal eye field and motor speech area(Broca).
What is the function of the insula?
Primary gustatory cortex.
What are the functions of the parietal lobe?
Primary somatosensory cortex(postcentral gyrus) and somatosensory association area.
What are the functions of the occipital lobe?
Primary visual cortex and visual association area.
What are the functions of the temporal lobe?
Primary auditory cortex, auditory association area and primary olfactory cortex.
What and where are the two areas for language comprehension intelligence and word formation?
Wernicke’s area(parietal lobe) and broca’s area(frontal lobe).
What are the 7 main functions of the left hemisphere?
Verbal memory, speech, right hand motor control, feeling shapes with right hand, superior language/mathematical comp and right visual field.
What are the 6 main functions of the right hemisphere?
Memory for shapes, left hand motor control, feeling shapes with left hand, musical ability, recognition of faces and spatial relationships and left visual field.
What are the base functions of each lobe?
Occipital, vision. Parietal, sensory. Frontal, motor. Prefrontal cortex, reasoning and decision making. Temporal, auditory.
What are the four sensory areas(cortex)?
Primary somesthetic cortex(parietal), primary gustatory cortex(parietal), primary visual cortex(occipital), primary auditory cortex(temporal).
What are the four association areas?
Olfactory association area(prefrontal), somesthetic association area(parietal), visual association area(Occipital), auditory association area(temporal).
What are the three types of tracts?
Projection(2), commissural and longitudinal fasciculi.
What is the function of basal ganglia?
Fine turn muscle contract(it’s the gray matter inside the white matter).
What are the functions of diencephalon?
Provides relays+switching centers for sensory, motor, visceral pathways.
The diencephalon contains what three parts?
Thalamus, epithalamus, hypothalamus.
What is the function of the hypothalamus?
Control autonomic nervous system, control endocrine. Regulate temperature and behavort/water intake4/sleep cycle.
What is the name of the stalk of the pituitary that extends from hypothalamus?
Infundibulum.
What is the reticular formation for motor and what is the function?
Part of the spinal cord(motor tone) that controls mental state.
What is the reticular formation for sensory?
RAS, mental awareness and sleep/arousal.
What are the four states of consciousness?
Alertness, wakefulness, sleep and coma.
What are the four parts of the limbic system?
Cingulate gyrus(emotion), thalamus, hippocampus(memory and learning), amygdala( emotional memory).
What are the three main functions of the limbic system?
Long term memory formation and storage, stores and codes emotional memory, smells associated with memory and emotion.
What are the structural changes to synapse during long term memory?
Increase in axon terminals, synaptic vesicles, receptors and synaptic efficiency. This is called potentiated.
Where do cranial nerves originate from?
Part of PNS originates from the brain.
What are the first three cranial nerves?
CN I olfactory nerve : Sense of smell.
CN II optic nerve : Sense of vision
CN III oculomotor : Muscle that moves the eye, lifts eyelids and controls pupil
What are the 4-6 cranial nerves?
CN IV trochlear nerve : controls superior oblique eye muscle.
CN V trigeminal : somatic sensation from face (chewing).
CN VI abducens nerve : controls lateral rectus muscle that abducts eye.
What are the 7-9 cranial nerves?
CN VII facial nerve : controls facial expressions, signals for taste of tongue.
CN VIII vestibulocochlear nerve : senses of hearing + equilibrium.
CN IX glossopharyngeal nerve : taste and touch from tongue; controls pharynx muscle.
What are the 10-12 cranial nerves?
CN X vagus nerve : visceral cessation, parasympathetic nerve to many organs of the body.
CN XI accessory nerve : controls next and pharynx.
CN XII hypoglossal nerve : controls tongue muscle.
What are the three functions of the spinal cord?
Sensory and motor innervation of the body inferior to the head. Ascending and descending tracts(conduction pathways). Integration center for spinal reflexes.
What is the purpose of the spinal cord?
Reflex and the spinal cord is the pathway for messages sent by the brain to the body and from the body to the brain.
Cauda equina is the strands/branches of the spinal cord.
Conus medullaris is where the spinal cord splits originally.
There are two enlargements at __ and __ for the spinal cord.
Lumbar and Cervical.
What is the name of the two parts of the medial line in the spinal cord?
Dorsal medial sulcus(outside) and ventral median fissure(inside).
What are the four parts of gray matter in the spinal cord?
Gray commissure(contains the central canal), dorsal horn, ventral and lateral horn.
Gray matter in the spinal cord is for ?
Axon moves in and out.
What are the two roots in the spinal cord?
Dorsal and ventral roots.
When the two roots combine together it is now called?
Spinal nerve.
The protruding area in the dorsal root is called the?
Dorsal root ganglion.
The function of the dorsal root ganglion is to?
Contain cell bodies of the sensory neuron.
The ventral root does not contain ganglion so its function is?
Motor. The cell bodies are in the spinal cord.
What are the three white matter parts of the spinal cord?
Dorsal funiculus, ventral funiculus and lateral funiculus.
What is the function of white matter in the spinal cord?
Moving information up and down the spinal cord.
The dorsal root and the dorsal horn receives?
Interneurons receiving input from somatic sensory neurons.
The ventral horn contains?
Interneurons receive input from visceral sensory neurons from the dorsal root. It also contains visceral motor(automatic neurons)
The lateral horn contains?
Somatic motor neurons
Ventral roots contain what two motor neurons?
Somatic and visceral motor neurons(tells smooth, skeletal and cardiac muscles to contract).
Dorsal roots contain?
Somatic and visceral sensory neurons.
After spinal nerve it becomes?
Ventral and dorsal ramus(both sensory and motor functions).
Dermatome maps show where each spinal nerve affects.
What are nerve plexuses?
Network of interweaving anterior rami and spinal nerves.
What are the four main plexuses?
Cervical, brachial, lumbar and sacral plexuses.
What is the function of plexuses?
To prevent deprive muscle or skin region of loss of motor or sensory.
Cervical is around your hyoid.
Brachial is around C5 an T1.
What are the three important nerves that branch from the brachial plexus?
Median(center) nerve, radial nerve and ulnar(funny bone) nerve.
Lumbar plexus is around?
L1 to L5.
Lumbar plexus contains one important nerve called?
Femoral nerve.
Sacral plexus is where?
L4 to S4.
Sacral plexus contains one important nerve called?
Sciatic nerve.
What are the characteristics of reflexes?
Involuntary responses, stimulus is required and response is rapid(chain of very few neurons). Reflex is a survival mechanism.
What are the five steps in the reflex arc?
Stimulus, sensory neuron propagated through spinal cord, nerve signal is processed in the horn(spinal cord and interneuron), then nerve signal is propagated by motor neuron to effector, effector response.
What is the reflex arc?
Neural pathway responsible for generating the response.
What are the differences between monosynaptic and polysynaptic reflexes?
Mono has a direct communication between sensory and motor neurons. Poly contains interneuron that facilitates sensory motor communication.
What are the spindle reflexes?
Reflexive contraction of a muscle after it is stretched. The stretch is detected by a muscle spindle(gamma motor neurons). This is a polysynaptic.
What are the four types of stretch reflexes?
Spindle somatic, ipsilateral and innate.
What do spinal reflexes prevent?
Prevents muscles from contrasting excessively.
What does golgi tendon reflex prevent?
Excessive muscle contraction. Located in the tendon. Golgi tendon organ detects tension. This is polysynaptic.
What is withdrawal reflex?
Pulls the body away from painful stimulus.
What is the crossed extensor reflex?
Conjoined with withdrawal reflex to keep the body steady(not fall).
What are the two diagnostics for unusual reflexes?
Hypoactive and hyperactive reflex.
