Term
| Function of the Nervous System |
|
Definition
| The nervous system is the main control and the regulatory system of the body. It communicates electrically and chemically to send messages very quickly from the Central Nervous System to the periphery of the body and from the periphery of the body to the CNS |
|
|
Term
|
Definition
| specialized structures that detect changes=sensory input(temperature, pressure, touch, etc.)Examples would include the eyes, Merkel/tactile cells, ears, temperature and pain receptors |
|
|
Term
|
Definition
| nerve pathway through which the sensory input is transmitted to the CNS. Formed by axons of sensory neurons |
|
|
Term
|
Definition
| structure (CNS) that analyzes the sensory input and makes decisions to respond to the change. Decision is made by interneurons, also called association neurons |
|
|
Term
|
Definition
| nerve pathway through which motor output is sent away from the CNS. Carried by axons of motor neurons |
|
|
Term
|
Definition
| carry out decision (motor output). Examples: skeletal muscles contract; smooth muscle relaxes blood vessels; glands produce sweat. |
|
|
Term
|
Definition
| this division mainly controls skeletal muscles in the body. It is voluntary |
|
|
Term
|
Definition
| this division is also called rthe visceral division. It carries signals to internal organs (viscera) like glands, cardiac muscles, and smooth muscles. It is in voluntary |
|
|
Term
|
Definition
| Brain (enclosed and protected by the cranium) and spinal cord (enclosed and protected by the vertebral column) |
|
|
Term
|
Definition
| nerves (spinal and cranial) and ganglia (dorsal root ganglion). Has sensory (afferent) and motor (efferent division). Also has somatic and visceral (autonomic) division |
|
|
Term
|
Definition
| this neuron has an extension coming off the soma that divides into a dendrite and an axon. Seen in sensory neurons of dorsal root ganglion. |
|
|
Term
|
Definition
| Has one dendrite and one axon. Rare form. Found in sensory organs (olfactory receptor/smell) |
|
|
Term
|
Definition
| this is the most common neuron. Multipolar neurons have many more branches of dendrites than the other two neuron types but only one axon. Found mostly in CNS. |
|
|
Term
|
Definition
| are receiving regions of neurons. Local potentials are usually created on dendrites and then travel to axon hillock |
|
|
Term
|
Definition
| this part of the neuron contains the nucleus and other organelles |
|
|
Term
|
Definition
| are conducting regions of neurons. Can have a myelin sheath (myelinated axons/fibers) or lack a myelin sheath (unmyelinated axons/fibers) |
|
|
Term
|
Definition
| located in the gray matter of the brain and spinal cord. If they are located outside CNS, those places are called ganglia |
|
|
Term
| 4 types of CNS glial cells and give their functions |
|
Definition
| Oligodendrocytes, Ependymal cells, Microglia, Astrocytes |
|
|
Term
|
Definition
| form the myelin sheath in the brain and the spinal cord |
|
|
Term
|
Definition
| line the cavities of the brain (ventricles) and spinal cord (central canal) |
|
|
Term
|
Definition
| phagocytize and destroy microorganisms, foreign matter, and dead nervous tissue |
|
|
Term
|
Definition
| have the most functions. Participate in forming the BBB |
|
|
Term
|
Definition
| these glial cells have as many as 15 arm like projections. These projections reach out to surrounding nerve fibers and form the myelin sheath around different axons |
|
|
Term
|
Definition
| these cuboidal epithelial cells are great for lining the internal cavities of the brain and spinal cord. These cells produce the cerebrospinal fluid (CSF) that bathes the CNS and its cavities with the nutrient rich fluid |
|
|
Term
|
Definition
| these cells have a soma with many fingerlike projections. These projections allow them to probe, attach, and destroy cellular debris or foreign material that they come across |
|
|
Term
|
Definition
| the most abundant glial cells that have a stra-shaped appearnace with arm like projections to connect to capillaries in the brain. Form a tight seal called the blood-brain barrier |
|
|
Term
| 2 types of glial cells found in the PNS |
|
Definition
| Schwann cells and Satellite cells |
|
|
Term
|
Definition
| these glial cells form the neurilemma and the myelin sheath around all PNS nerve fibers |
|
|
Term
|
Definition
| provide electrical insulation and regulate chemical environment of neurons |
|
|
Term
|
Definition
| this cell wraps itself around individual nerve fibers forming the internodes. Portions not covered by the cell are called nodes of Ravier |
|
|
Term
|
Definition
| these cells surrounded the somas. Their thick covering protects the soma much like the Schwann cells protect the nerve fiber by providing electrical and chemical regulations |
|
|
Term
| what is the ratio of neuroglia to neurons |
|
Definition
|
|
Term
|
Definition
| the ability to transport/allow solutes through a membrane |
|
|
Term
| ion channels affect neuron selective permeability |
|
Definition
| When ion channels are open, permeability of plasma membrane is increasing. When ion channel are closed, solutes will not be able to pass through |
|
|
Term
|
Definition
| ECF concentration is high, ICF is low |
|
|
Term
|
Definition
| ICF concentration is high, ECF concentration is low |
|
|
Term
|
Definition
| ECF concentration is high, ICF concentration is low |
|
|
Term
|
Definition
| unequal distribution of ions across the plasma membrane due to its selective permeability. Normally permeable to Na and K (due to constantly open channels) and not permeable to cytoplasmic anions (PO4-, SO4-, organic acids, and proteins) |
|
|
Term
|
Definition
| a voltage difference across the plasma membrane due to unequal distribution of ions, selective permeablity of membrane and Na/K pump. has the "potential" to cause a flow of ions |
|
|
Term
| constantly open ion channels |
|
Definition
| are always open and allow ions to move in and out of the cell as long as the solute fits through the channel opening |
|
|
Term
|
Definition
| these channels open in response to signals |
|
|
Term
| ligand-gated ion channels |
|
Definition
| open in response to chemicals attaching to them (ex. ligand gated Na channels on junctional folds of NMJ) |
|
|
Term
| voltage gated ion channels |
|
Definition
| open in response to voltage change (ex. voltage gated Na channels on the axon hillock, forming the trigger zone) |
|
|
Term
| voltage gated Na channels and voltage gated K channels |
|
Definition
| the voltage gated channels that are essential for the development of the action potential |
|
|
Term
|
Definition
| a minimum change in voltage across the permeable membrane (around -55mV) that can open voltage gated Na and K channels and generate an action potential (nerve signal) |
|
|
Term
| absolute refractory period |
|
Definition
| period of absolute resistance to stimulation: absolutely no stimulus will trigger an action potential |
|
|
Term
| relative refractory period |
|
Definition
| period of relative resistance to stimulation: only strong stimulus will trigger an action potential |
|
|
Term
| Presynaptic neuron and postsynaptic neuron |
|
Definition
| what are the pre and post synaptic cells at the synapse |
|
|
Term
| structures that comprise a chemical synapse |
|
Definition
| synaptic knob, synaptic vesicles, voltage gated Ca channel, synaptic cleft, receptors |
|
|
Term
|
Definition
| in myelinated fibers, action potential is ONLY formed in nodes of Ranvier and then skips over the internodes. Saltatory means to jump, just as the signal jumps over the myelin sheath to the next node of Ranvier. Walking normally, much faster |
|
|
Term
|
Definition
| the end of the axon, looks like a swelling, holds vesicles with NT. allows for transmitting chemical signals throughout the body |
|
|
Term
| Excitatory Cholinergic synapse |
|
Definition
| this is a synapse in which acetylcholine is the main neurotransmitter. Ach is seen in NMJ, where it is responsible for activating skeletal muscles. It is also seen in other parts of nervous system. Ach opens ligand gated Na channels that depolarize the postsynaptic cell. Depolarizaion means excitation |
|
|
Term
| Inhibitory GABAergic synapse |
|
Definition
| this synapse uses y-aminobutyric acid (GABA) as neurotransmitter. GABA opens ligand gated Cl channels that hyperpolarize the postsynaptic cell. Hyperpolarization takes the cell away from the threshold, thus the cell is inhibited and the synapse is called inhibitory |
|
|
Term
| Excitatory postsynaptic potential (EPSP) |
|
Definition
| graded depolarization, will bring a normal Vm closer to the threshold. Neuron is more likely to fire, so neuron is excited |
|
|
Term
| Inhibitory postsynaptic potential (IPSP) |
|
Definition
| graded hyperpolarization, will bring a normal Vm farther away from the threshold. Neuron is less likely to fire, so neuron is inhibited |
|
|
Term
|
Definition
| ONE presynaptic neuron stimulates postsynaptic neuron multiple times within a brief period of time. All these stimulations are added. If their sum brings neuron to threshold, postsynaptic neuron will fire |
|
|
Term
|
Definition
| multiple presynaptic neurons all stimulate ONE postsynaptic neuron. All these stimulations are added. If their sum brings the neuron to threshold, neuron will fire |
|
|
Term
|
Definition
| caused by opening of ligand-gated channels, are graded, are reversible, travel short distances, are decremental, can excite or inhibit the cell |
|
|
Term
|
Definition
| caused by opening of voltage gated channels, are irreversiblel are all or none, travels long distances; are non decremental |
|
|
Term
| Excitatory Neurotransmitter in the CNS |
|
Definition
| norepinephrine and epinephrine |
|
|
Term
| Inhibitory Neurotransmitter in the CNS |
|
Definition
| y-aminobutyric acid (GABA) |
|
|
Term
|
Definition
| the spinal cord is thicker here than in other areas as it provides additional innervation to the upper and lower limbs |
|
|
Term
|
Definition
| is located in the inferior cervical region, these branches innervate the upper limbs |
|
|
Term
|
Definition
| found in the lumbosacral region, these branches give rise to the nerves for the lower limbs and pelvic region |
|
|
Term
|
Definition
| the inferior most part of the spinal cord, the end of the spinal cord at the level L1-L2 |
|
|
Term
|
Definition
| the bundle of nerve roots that occupy the vertebral canal from L2 to S5 |
|
|
Term
|
Definition
| a cordlike organ composed of multiple axons ensheathed in connective tissue latyers seen in the peripheral nervous system. Endoneurium surrounds each axon, perineurium surrounds a fascicle and epineurium surrounds the entire nerve |
|
|
Term
|
Definition
cervical-8
thoracic-12
lumbar-5
sacral-5 usually fused
coccygal-1 |
|
|
Term
| Spinal Nerve (Types of Fibers) |
|
Definition
| they carry both sensory (afferent and motor (efferent) fibers |
|
|
Term
| Spinal Nerves (proximal branches) |
|
Definition
| posterior (dorsal) root and anterior (ventral) root |
|
|
Term
| Spinal Nerves (distal branches) |
|
Definition
| Anterior ramus and Posterior Ramus |
|
|
Term
|
Definition
| has posterior horn, gray commissure, lateral horn, and anterior horn. Its appearance is similar to a view of a butterfly with open wings. Has somas and dendrites of neurons |
|
|
Term
|
Definition
| extends toward the spinous process of the vertebra |
|
|
Term
|
Definition
| a section of gray matter that extends towards the vertebral body |
|
|
Term
|
Definition
| a section of gray matter that connects the right and left halves of the spinal cord around the central canal |
|
|
Term
|
Definition
| made up of the posterior column, lateral column, and anterior column. Has axons |
|
|
Term
| Posterior (faniculi) column |
|
Definition
| this is the column between the dorsal horn and the posterior median sulcus |
|
|
Term
| Lateral (faniculi) column |
|
Definition
| this is the location of the axon bundles between the dorsal and lateral horn |
|
|
Term
| Anterior (faniculi) column |
|
Definition
| this is the region between the anterior horn and the anterior median fissure. IN the columns, we find multiple tracts |
|
|
Term
|
Definition
| a group of axons in the CNS that have similar origin, destination, and function |
|
|
Term
|
Definition
| carry sensory information up the cord towards the brain |
|
|
Term
|
Definition
| conduct motor impulses down the spinal cord towards effector organs |
|
|
Term
|
Definition
| a shallow longitudinal groove along entire length of spinal cord, on posterior side |
|
|
Term
|
Definition
| a deeper longitudinal groove along entire length of spinal cord, on anterior side |
|
|
Term
|
Definition
| is found in the middle of gray commissure. It is lined with ependymal cells, and is filled with CSF |
|
|
Term
|
Definition
| contains cell bodies of sensory neurons of afferent spinal nerves |
|
|
Term
|
Definition
| passes posteriorly through the intervertebral foramen towards the back of the spinal cord and then enters the posterior horn of the cord, has sensory fibers ONLY. Expands into the posterior root ganglion |
|
|
Term
|
Definition
| passes anteriorly toward the front of the front on the spinal cord, consists of axons of motor neurons located in ventral horn, has motor fibers ONLY, does not have ganglion |
|
|
Term
|
Definition
| these are the nerves arising from the dorsal and ventral roots that branch many times in order to innervate the body, all are mixed nerves |
|
|
Term
|
Definition
| formed from the Anterior Ramus of C1-C5 nerves. mostly cutaneous and sensory innervation of the head and lateral neck, shoulders, and anterior chest, pleura, and pericardium. Also innervates some of the muscles of the diaphragm and head/neck muscles. ex. phrenic nerves |
|
|
Term
|
Definition
| formed by the anterior ramus of the nerves C5-T1. lots of cutaneous, joint, and muscular innervations of the upper limbs. ex. radial and ulnar nerves |
|
|
Term
|
Definition
| formed by anterior rami of nerves L1-L4. lots of cutaneous, joint, and muscular innervations of the upper regions of the lower limbs. ex: femoral, obturator nerves |
|
|
Term
|
Definition
| formed from the anterior rami of nerves L4,L5 and S1-S4. mainly cutaneous, joint, and muscular innervations of the lower limbs and pelvic region. ex:sciatic |
|
|
Term
|
Definition
| cutaneous regions innervated by one spinal nerve |
|
|
Term
|
Definition
| quick involuntary, stereotyped reactions of glands and muscles to stimulation |
|
|
Term
| intrinsic (inborn) vs. acquired (learned |
|
Definition
| intrinsic are reflexes we are born with for primitive protection. A baby will close its eyes when a bright light is introduced but would not have an acquired reflex to know how to ride a bike |
|
|
Term
|
Definition
| somatic reflexes are responses of the skeletal muscles while visceral deal with internal organs |
|
|
Term
| monosynaptic vs. polysynaptic |
|
Definition
| monosynaptic reflexes have one neural synapse between two neurons. This is commonly between a primary sensory neuron and a motor neuron. No interneurons are involved. Faster. Polysynaptic reflexes on the other hand have two or more synapses between three or more neurons in a pathway. Inerneurons are involved. slower. |
|
|
Term
| Ipsilateral vs. contralateral |
|
Definition
| ipsilateral reflexes are those where the sensory input and the motor output stay on the same side of the body. Contralateral reflexes are those that have the sensory input on one side and motor output on the opposite side of the body |
|
|
Term
|
Definition
| reflex mediated by the spinal cord (involves spinal nerves) |
|
|
Term
|
Definition
| reflex mediated by the brain (involves cranial nerves) |
|
|
Term
|
Definition
helps maintain equilibrium and posture because as a muscle is stretched it contracts in response. Ipsilateral
-muscle spindles send afferent signals to the brain. The brain then sends efferent signals back to the muscles |
|
|
Term
| Flexor (withdrawal) reflex |
|
Definition
this is a quick contraction of flexor muscles whixh results in retracting or withdrawing the limb from a possibly dangerous stimulus. Ipsilateral
-pain receptors send a message from the site to the spinal cord. Motor neurons excite the flexor muscle to contract and withdraw the limb |
|
|
Term
|
Definition
contraction of extensor muscles in the opposite limb from the one being withdrawn
-Branches of the afferent nerve fibers cross from the injured side of the body to the contralateral side of the spinal cord |
|
|
Term
| Demonstration of a stretch reflex (Patellar reflex) |
|
Definition
| commonly known as a knee-jerk reflex. When a physician strikes the patella with a tendon hammer it stretches the ligament |
|
|
Term
| Location and function of the 1st, 2nd, and 3rd neuron in the sensory pathway |
|
Definition
| these neurons found in the ascending tract and carry sensory signals to the CNS |
|
|
Term
|
Definition
| found in the dorsal root ganglion; detect stimuli and transmits signal to the spinal cord or brainstem |
|
|
Term
|
Definition
| found in the dorsal horns; forward the signal on to the thalamus at the upper end of the brainstem |
|
|
Term
|
Definition
| found in the thalamus; carry the signal to the rest of the cerebral cortex's sensory region |
|
|
Term
|
Definition
| many are located in the cerebral cortex and have an axon that terminates on a lower motor neuron. the starting place of efferent signals |
|
|
Term
|
Definition
| mostly located in ventral horns. their axon travels all the way to the muscle or target organ. ending point of efferent signal in effector |
|
|
Term
|
Definition
| Cerebrum, Cerebellum, Brainstem |
|
|
Term
|
Definition
| 83% of the brain volume; it is composed of the right and left cerebral hemispheres |
|
|
Term
|
Definition
| found caudal to the cerebrum; in the posterior cranial fossa; it is the second largest region of the brain |
|
|
Term
|
Definition
| all the brain parts left if the cerebrum and cerebellum were to be taken away; its major components are the diencephalon, midbrain, pons, and medulla oblongata |
|
|
Term
|
Definition
| in the spinal cord is located in the center of the spinal cord and is made up of the posterior horn, gray commissure, lateral horn, and anterior horn. Gray matter in the brain forms an additional surface layer called the cortex over the cerebrum, cerebellum, as well as deeper masses located in white matter called nuclei |
|
|
Term
|
Definition
| in the spinal cord found surrounding the gray matter. IN the brain the white matter is found deep to the cortical gray matter and superficial to the gray matter surrounding the cavities of the brain |
|
|
Term
| 5 lobes of the cerebral cortex |
|
Definition
| Frontal Lobe, Parietal Lobe, Occipital lobe, Temporal Lobe, Insula |
|
|
Term
|
Definition
| is located rostral to the central sulcus. Has the precentral gyrus found rostral to the central sulcus. Responsible for movement, parts of speech, has motor homunculus, and personality |
|
|
Term
|
Definition
| located caudal to the frontal lobe and to the central sulcus. Has th epostcentral gyrus found just caudal to the central sulcus. Responsible for sensory perception, has the sensory homunculus |
|
|
Term
|
Definition
| found just caudal to the parietal lobe. Responsible for visual processing (vision) |
|
|
Term
|
Definition
| the most inferior lobe located inferior to the lateral sulcus. Responsible for hearing and memory |
|
|
Term
|
Definition
| small mass of cortex deep in the lateral sulcus and canbe found by retracting the cerebrum covering it. Little is known about its function because of its location |
|
|
Term
| Cerebral hemispheric lateralization (categorical) |
|
Definition
| LEFT- specialized for spoken and written language, and sequential and analytical reasoning used in science and math, this hemisphere breaks information into fragments and analyzes it literally |
|
|
Term
| Cerebral hemispheric lateralization (Representative) |
|
Definition
| RIGHT- specialized for imagination, insight, musical, and artistic skill, perception of patterns and spatial relationships, and the comparison o f sights, sounds, smells, and tastes |
|
|
Term
|
Definition
| thick bundle of nerve fibers located deep in the longitudinal fissure that connects the left and right hemispheres of the cerebrum and allows for interhemispheric communication: lets the right hemispher know what the left one is doing and viceversa |
|
|
Term
|
Definition
| in the brain has a double layer membrane: the outer layer lines the bones of the skulls; the inner layer forms partitions to separate parts of the brain |
|
|
Term
|
Definition
| loose spider-web like lining of dura mater, similar in brain and spinal cord. Participates in subarachnoid space |
|
|
Term
|
Definition
| a highly vascularized layer that clings tightly to the brain and spinal cord. Very delicate |
|
|
Term
| Functions of Cerebrospinal fluid |
|
Definition
Buoyancy: allows brain to float in fluid, thus reducing the weight and preventing damage from pressure Protection: prevents the brain from striking the skull in a blow to the head
Chemically stability: CSF rinses metabolic wastes from the nervous tissue and regulates the chemical environment of the brain |
|
|
Term
| Cerebrospinal fluid (Produced) |
|
Definition
| about 500ml/day, 30% from general ependymal lining of the brain ventricles, 30% from the choroid plexuses, and 40% from the subarachnoid space |
|
|
Term
| Cerebrospinal fluid (circulation) |
|
Definition
| continually flow through and around CNS. It is driven by its own pressure, by beating of ependymal cilia, and partly by rhythmic pulsations of brain from the heart beat |
|
|
Term
| Cerebrospinal fluid (Re-absorption) |
|
Definition
| CSF is constantly reabsorbed at the same rate as it is being produced. it happens in the arachnoid villi |
|
|
