Bio 669 Quiz 2 with complete solutions, Exams of Advanced Education

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Bio 669 Quiz 2 with complete solutions

Neuron is composed of dendrite, cell body (middle portion of neuron) , axon densely packed cell bodies (of the neuron, which is middle part) in the CNS are called

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nuclei nucleus located in CNS Read More densely packed cell bodies in the PNS are called _____ Ganglia What are dendrites? Receptive portions of the neuron; receives incoming information, senses external stimuli then sends signal to cell body of the neuron What do axons do? Carry impulses away from the cell body to the affector or to another neuron. action potential starts here because lowest threshold for stimulation is membrane potential about the inside of the cell or the outside? inside of the cell what is an electrochemical gradient? describes the forces affect on ion movement if allowed to become a permeable membrane which way the ion moves when does action potential start? when a membrane is depolarized enough that it triggers voltage-gated ion channels What is a graded potential? changes in membrane potential that decreases over distance rather the inside is - or + resting state of the membrane is related to an imbalance of ions, maintained by ion pumps, and a decrease in? permeability Na channells are closing reducing amount of Na availabel to change the inside charge to allow for depolarization (resting potential) refractory period polarizatoin or seperation of ions and charges create an electrical potential. ____________ separation causes polarization and a __________ separation causes depolarization. increase in separation

decrease in separation (ions are closer together, become stronger and can cause an action potential through depolarization) signals are conveyed through this polar membrane polarization refers to the ____________ of the cell where it is more negative? the difference is found at the membrane, not the whole cell. what ions cause this difference? inside ICF, ICF= - ECF= + Na, K. Mostly its caused from Na true or false, not all depolarization leads to an actions potential? True the gradient potential may not be able to create enough to self sustain movement which is termed a local event, depolarization can occur but not lead to an action potential Action potentials are self sustaining movement of a signal (stimuli) down a membrane. moving a membrane potential from -70mV to -50mV would be considered depolarization or polarization? Depolarization because they are becoming less separated, closer together or less different the charges are getting closer if a membrane is deplolarized enough to trigger ______________, an action potential starts. which the minimum needed for an action potential to occur is called the

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voltage gated channels threshold (epinephrine and acytelcholine triggers the opening of these channels thus making them more permeable to Na and K to move in and out. ______________ is a brief/temporary change in membrane potential that will decrease over time. can be hyperpolarization or depolarization depending on if they are occuring at the same time because of this occurs they will cancel each other out. (magnitude variant). Ion channels can open by chemical influence (epi, acetylcholine ) or by electrical potentials graded potentials ______________ look alike, they are all or none events, proceed the same way , proceed without decrement (not diminishing over time) and followed by a refractory period? Action potential ______________ is when the membrane rests after so many action potentials , needs to reset, and at his point, is unable to create another action potential?

______________ is when the membrane can generate an action potential but is very difficult to do so, is some opening of the K gates where it can be too hyperpolarized. absolute refractory period relative refractory period usually what Is a refectory period? a period immediately following stimulation that is unresponsive for some time. Reduced sensitivity (Na gates are closed to stop or slow movement of Na making reduced sensitivity) (depolarization) at this time K gates open and hyperpolarize the membrane. generating an action potential: _____________ gate open which cause depolarization increasing permeability which moves the ion (___ ) from outside to inside making the inside more positive therefore deplorazing because the K moves out of the cell to repolarize the membrane causing hyperpolazed state Na channels open What is myelin? A lipid insulating material surrounds nerve cell axon. formed and maintained by the Schwann cell in the PNS (which increase speed of action potential) what is myelin called in the PNS? Schwann cells What are the nodes of Ranvier? gaps in the myelin sheath between schwann cells. these areas have a lot of ion channels to assist in regeneration of an action potential. allow ions to diffuse in and out of the neuron to the axon. allows for saltatory conduction. What is saltatory conduction? this only occurs on Nodes of Ranvier of the exposed plasma. The flow of ions between segments of myelin rather than along the entire length of the axon. Like playing leap frog. AP jumping from one node to another node speeding up the AP What is divergence? An axon signaling pathway ability of branching axons to influence many neurons. where one signal converts into more signals where it can affect more neurons What is convergence? another Axon signaling pathway

Branches of numerous neurons converging on one or a few neurons multiple neurons converge on one another which makes the signal stronger Central Nervous System (CNS) is made up of brain and spinal cord Peripheral Nervous System (PNS) is made up of cranial nerves and spinal nerves afferent pathways are_____, sensory signals going up to the brain ascending efferent pathways are _____, motor signals coming from the brain outward to the body like to skeletal muscles descending What does the somatic nervous system do? found in the PNS motor and sensory pathways that regulate voluntary motor control of the skeletal muscles What does the autonomic nervous system do? found in the PNS. this is then broken down into the ____________ and ____________ -motor and sensory pathways involuntary control or organ systems. -Sympathetic - fight or flight -Parasympathetic- involves rest, digestive system , regulating glands, smooth muscle, secretions, vasomotor tone ______________ pathway gives feedback from the gut and organs back to the brain but dont conduct a lot of signals.? visceral sensory pathway What is Wallerian degeneration? lose distal aspect of an axon and will causing swelling, lose of myline sheath Nerve injury : separated/degeneration of a nerve fiber by injury or disease, stroke, tumers, lesions (injury occurs at proximal end, but will effect the distal end of the axon,) can be caused by sitting too long from the pressure exerted on the leg where a nerve may be if a nerve injury occured at the proximal site, where cell body would be, what would happen? swelling, nissi substance, increase protein synthesis and mitochondrial activity and see terminal sprouting (a way for the neuron to regenerate is to sprout surviving (intact) motor axons send axon terminals (sprouts) to the denervated muscles in an attempt to reinnervate these muscle fibers and restore muscle power. This is a quick and effective method of reinnervation that applies only to partial axon loss lesions where some axons escape injury and wallerian degeneration regeneration of nerves depend on the location, inflammatory response, and scar tissue. True or false True generally seen in PNS and limited to myelinated axons

_____________ is a cellular constitute of a neuron that if changed like in alzheimers disease cause neurofibrillary tangles neurofibrils What is a synapse? Gap between neurons, a junction where conducting action potentials from one neuron to the next occurs by chemical (neurotransmitters) or electrical conduction. , these can be chemical to induce opening of the channels from another neuron that can create an effect on that neuron. (are between neurons to allow sharing of the signal) Other neurons are influenced by the release of neurotransmitters Neurons generate and conduct electrical and chemical impulses by selectively changing the electrical potential of their plasma membranes and influencing other nearby neurons by the release of neurotransmitters The synaptic boutons is a presynaptic terminal or end of the axon where ______________ is stored? neurotransmitters are sent to the ___________ of the synapse along with increase in Ca to create an environment condusive for an action potential to occur if there is enough chemicals released and if it can be sustained can depolarize enough to generate the AP neurostranmitters are stored synaptic cleft True or false, all drugs to date target a protein? different drugs affect different neurotransmitters true targets a protein receptor on the neuron which leads to the high and can lead to an addiction. stimulate the reward pathway that leads to the addiction and drug seeking behavior What is temporal summation of a synapse? time single presynaptic neuron involves produces multiple subthresholds over a period of time. At a certain point, the sum of these subthreshold become sufficient for the generation or firing of an action potential occurs when a single presynaptic neuron fires many times in succession, causing the postsynaptic neuron to reach its threshold and fire What is spatial summation? distance Spatial summation occurs when excitatory potentials from many different presynaptic neurons (from a distance) cause the postsynaptic neuron to reach its threshold and fire second messenger system (can be excititory or inhinitory) affects the muscarinic cholinergic receptor)

Receptors (ligane) may be this kind, meaning they activate another molecule inside the cell to make changes. occurs because the first messenger wasn't able to. need a receptor to send a signal across the membrane which is a ligane second messenger system one messegner binds on the outside, then activated a 2nd messenger (receptor) and releases it on the inside and has a cascade affect inside the cell. what is an example G protein linked receptor opiods acutely reduce the effectiveness of _____________ production via second messenger causing the HIGH. if you keep taking it , over time this reduction will get less reduction in the 2nd messenger leading to _______________ this causes you to have to take more and more to get the same affect as before (tolerance)

• cAMP -dependence rewards centers stimulate seeking behaviors in the brain which feed off enjoyable behaviors. these are located in the? limbic system (amygdala, hippocampus and frontal cortex) like gambling, drug addiction sex. ______________ in a synapse are considered a neurotransmitter but if they are released by the adrenal gland into the bloodstream, they act as hormones? epi/norepi _____________ , epinephrine and norepi are considered catecholamines that are developed from tyrosine Dopamine the amino acid ______________, can be modified by a few enzymes to form Ldopa which can be converted into dopamine which is used in treating parkinson. will see damage to basal ganglia Tyrosine There is a lack of dopamine released in areas of the brain in parkinson. giving Ldopa can help supplement the loss of dopamine. dopamine can be further converted into norepi. _______________ in the brain remove or breakdown neurostransmitters such as norepi, serotonin, and dopamine (CNS) which can lead to depression, anxiety. -monoamine oxidase tx- MAOIs inhibit the breakdown of the neurotransmitters What are some side effects of using MAOIs to txt parkinson, anxiety and depression? weight gain, loss of sex drive, appetite changes, blurred vision, dry mouth, serotonin syndrome, increased Bp What is the reticular formation?

Network of connected nuclei that regulate vital reflexes, such as cardiovascular and respiratory function. wakefulness, and consciousness with the cerebral cortex, they form the reticular activating system, Central Nervous system: match the correct answer

1. connects the body to the brain and relay information back and forth.
2. deals with conscious thought and voluntary actions
3. reflex actions, autonomic , Bp, RR a. Hindbrain b. midbrain c. forebrain
4. b midbrain (corpora quadrigemina, tegmentum, cerebral peduncles
5. c forebrain (have cerebral hemisphere where basal ganglia are that control movement) cerebrum
6. a Hindbrain (cerebellum, pons, medulla) ________________ area of the CNS and apart of the forebrain is responsible for movements such as in muscles that are used to create and form speech, speech comprehension? *the forebrain is the major bulk of brain mass, contains frontal, pariatal, occipital, temporal lobes of the brain -Brodmann area injury to brocha area can cause aphagia , inability to comphrehend or formulate language frontal lobe function (forebrain) where basal ganglia are in the cerebral hemi primary motor area and limbic systems, emotions conscious movement, planning, judging social norms This is underdeveloped with ADD parietal lobe (forebrain) somatic sensory input, sensation of feeling occipital lobe (forebrain) primary visual cortex, able to associate and understand what you see temporal lobe (forebrain) primary auditory cortex, allows you to understand what you hear and aid in fluent speech What is the basal ganglia? (cerebral nuclei) a group of structures linked to the thalamus in the base of the brain and involved in coordination of movement.. if these neuron cell bodys are damaged , you will see this in parkinson gray matter of the forebrain is found in the __________-- white matter is found in the _________________

in cerebral cortex in cerebral medulla

1. regulates the endocrine system?
2. Regulates sleep patterns, production of melatonin?
3. precieves sensations and relays the cerebral cortex a. hypothalamus b. thalamus c. epithalamus (pineal gland) 1.a
4. c
5. b ______________ is a progressive failure of cerebral function. will see a loss in orientation, short term memory, difficulty with language, impaired judgement & decision making, confusion? _________________ has three types -Early onset 40-50's, familial -nonhereditary, sporatic after 60's -increased amyloid precrsor protein, alteration in apolipoprotein E, will also see, fibrillary tangles from clump TAU proteins Dementia Alzheimers with alzheimers disease ________________ cause a decrease in brain mass and increase ventricular size. Will see fibrillary tangles from clump TAU proteins. will see a more defined deep grooved sulcus senile plaque what are some clinical manifestations of Alzheimers disease? forgetfullness emotional upset (labile, fly off the handle fast) confusion disorientation decline in abstract problem solving, and judgement ______________ a sudden transient alteration of the brain function caused by abnormal rapid firing of cortical neurons , a release of an axcessive amount of neurotransmitters? seizure epilepsy is seizure of unknown or unexplained cause, can have convulsions as seen in grandmal seizure, tonic-clonic- jerky, contraction and relaxing

____________ is a small seizure where someone may gaze off into the distance, fixed stare for short period of time? petitmal seizure Seizures: -prodromal phase scan prociede the seizure as much as a day -tonic = contraction,loss of conscciousness -clonic= relaxation

• ______________ phase follows a seizure, may experience depression, tiredness or a deep sleep afterwards.? ____________- is seizure lasting more than 5 mintutes? postictal phase status epilepticus _________________ disease is related to severe degeneration of the basal ganglia that involves dopaminergic pathway? clinical s/s include: stooped appearance (posture) tremors bradykinesia (slow movements) shuffle gate hallucinations depression -Parkinsons disease secondary parkinsons is caused by some type of trauma like in boxing or head injury upper motor neuron syndrome (brain damage) hemiparesis or hemiplegia one sided diplegia paraparesis and paraplegia 2 bottomlimbs quadriparesis or quadriplegia all 4 limbs pyramidal motor syndromes spinal shock spastity Paresis-loss of some muscle function, weakness Paralysis- total loss of function lower motor neuron syndrome Flaccid paralysis (loss of voluntary control but may have reflexes r/t unvoluntary moveents) /paresis, hypotonia, hyporeflexia, fibrillation (bundle of muscles contracting at one time) , muscle atrophy

Guillian Barre (by viral infection) -Bulbar Palsy (affects cranial nerves of face and neck, motor portions) -paralytic poliomylitits what are some examples of lower motor neuron syndromes? -Guillian Barre (by viral infection) -Bulbar Palsy (affects cranial nerves of face and neck, motor portions) -paralytic poliomylitits What is Amyotrophic Lateral Sclerosis (ALS)? The steven Hawkins disease AKA Lou Gehrigs disease etiology is unknown neurodegenerative disorder affecting upper and lower motor neurons, progressive muscle weakness and atrophy, loss of gait, fetal ***the senses and cognition however are intact What does flaccid mean? damage to anterior horn cells or ventral root, thus the muscle receives no signals at all. what is affected if there is spinal cord trauma between T1-L1 and what is this termed? if the injury is in the cervical region? -both legs, paraplegia -Quadraplegia What does spastic mean? damage to upper motor neurons in the motor cortex, allowing some sporadic stimulation from spinal chord reflexes. No voluntary control. involuntary reflexes will be seen What is paresthesia? loss of sensory function- tingling, numbness, pinns and needle feeling How many spinal nerves are there? 31 spinal cord connects the brain with the body, motor pattern control centers, sensory and motor functions and conducts _____________ and ______________ reflexes? somatic (skeletal muscles, voluntary) lower motor neuron autonomic (regulates viscera reflexes like Bp, HR, peristalsis, urination, smooth muscle, involve preganlionic and posganlionic CSF produced in the choroid plexus, 125-150ml in the ventricle. some meds cant cross into the CSF where in the spinal cord is a spinal tap or lumbar puncture given? where in the spinal cord is an epidural given? -penetrates the Dura mater (outer covering of cord) -given just outside the dura mater, doesn't penetrate

3 coverings of the spinal cord which make up the menninges: surrounds brain and spinal cord dura mater- outer layer arachnoid mater- middle layer pia mater- inner most layer how spinal nerves are named: c1-c7 are named based on the vertebrae _______________, and then C8, T, L,S and 1 C are named based on the vetebrae _____________? -vertebrae directly below it ( so spinal exits above the vertabrae C -vertebrae immediately superior. spinal cord trauma, compression of the roots, cause pain, weakness, and loss of feeling. what is the most common cause of this? herniated disc (also caused by osteoporosis, osteoarthritis, cancer or injury to the spinal cord) how many cervical spinal nerves are there? 8 how many thoracic spinal nerves are there? 12 how many lumbar spinal nerves are there? 5 how many sacral spinal nerves are there? 5 how many coccygeal spinal nerves are there? 1 cerebrospinal fluid is produced by the choroid plexus ________________ is a network of axons from anterior rami of adjacent nerves that join and then split. This occurs several times. Roots (anterior rami combined to form) Trunks Division (anterior and posterior division) then form, Cords, these then Branches where they exit nerves Plexus (brachial, cervical, radial, ulnar) ____________ has 4 components to be intact. Receptor Afferent neuron - sense change, signal change,sends up to brain efferent neuron- signal a response (sends signal to react from brain to the body) effector- gland/muscle that carry out the response reflex arc upper motor neurons arent apart of the reflex arc but influences it

lower motor neurons ARE apart of the reflex arc, direct influence on muscles __ ___________ will causes deep ridges, decrease acetylcholine which causes a decreased ability to signal muscles thus leading to muscle weakness from decrease signally and contraction? Myasthenia gravis will have antibodies against the acetylcholine recpetor leaving less to react or send signals to the face and eye, may see drooping eyes, double vision, problems swallowing tx: acetylcholinergic inhinitors ______________- is caused by an upper motor neuron lesion usually will partial loss or paralysis of voluntary muscles leading to spasticity or contractures. largest leading cause of crippling in children. temporary loss of 02, drugs, radiation cerebral palsey CP reflexes are intact just modified How many vertebrae are there? 33 (7 cervical, 12 thoracic, 5 lumbar, 5 sacral, 4 coccygeal) ______________- allows chemical to be released in the cleft to bind and diffuse to the acetylcholine plasma surface then releasing molecules outside the cell exocytosis What is the blood brain barrier (BBB)? cellular structures that selectively inhibit certain potentially harmful substances in the blood from entering the interstitial space of the brain or the CSF such as some drug cant cross the BBB What three arteries arteries help form the circle of willis, which can reroute blood flow to the brain if their is a blockage? they all connect together -posterior cerebral artery (occipital lobe, inferior surface of brain) -anterior cerebral artery (frontal lobe, superior and anterior surface of brain) middle cerebral artery (supplies major blood flow to the brain) blockage beyond circle of willis will lead to ischemia What are vesicles? bundles of myelinated axons in the PNS What is the autonomic nervous system? coordinates and maintains the steady state among the visceral (internal) organs involuntary smooth muscles ______________-- is an over the counter drug that mimics the sympathetic system. it mobilzes energy stores, increase lipolysis and metabolism. can be addictive ephedra (Ma huang) increases risk of MI, Stroke, increase Bp if taken for long periods of time ______________ receptors binds to nicotine and acteylcholine. they are only found in skeletal muscle?

nicotinic receptors most organ systems use both sympathetic and parasympathetic invervations excepts the ___________ system which only has sympathetic invervations? vascular system What is a preganglionic neuron? a motor neuron of the autonomic system. in CNS and PNS myelinated how many pairs of cranial nerves are there? 12 pairs of cranial nerves What is a postganglionic neuron? motor neuron of the autonomic system. in CNS and PNS. unmyelinated demyelination slows down the AP affecting sensation and motor function a sympathetic postganglionic fiber contains what neurotranmitter? Sympathetic preganlionic fiber? in the parasympathetic, the post/preganlionic fibers contain? -norepi, bond to adrenergic recptors always exitaotry -acetylcholine, bonds to cholinergic receptors (muscutinic and nicotinc receptors) excittory or inhiitory -acetycholine and bonds to cholinergic receptors What is the sympathetic nervous system? part of autonomic nervous system. "Fight or flight" Blood pressure/heart rate increase, digestive slowing. epi has affects on liver cells, binds to beta adrenergic receptors activates G protein, cAMP cause glyconeogenisis raises glucose Autonomic nervous system: sympathetic and parasympathetic What is the parasympathetic nervous system? part of the autonomic nervous system. has. "Rest and digest" Blood pressure/heart rate decrease, digestive increases/motility , decrease phincter tone both parasympathetic and sypathetic work at the same time, if one is remove the other will be exaggerted We have an expert-written solution to this problem! heart parasympathetic decreases rate; slows and steadies heart sympathetic

increases rate and force of heartbeat GI tract parasympathetic increased motility, secretions, and opens sphincters diahrrea, cramping Effect of the autonomic nervous system ANS: Skeletal muscle aterioles of the SNS effect? abdominal viscera of the SNS effect? lungs SNS effect? lungs PNS effect? *beta- binds to epi, vasodilate relax smooth muscle alpha 1- vasoconsticts constrict smooth muscle increase Bp *vasocontrict abd visceral arteries, *sns- vasodilation of bronchioles pns- vasocontstict bronchioles give epi in anaphylaxis cause if vasodilates bronchioles alpha 1= ALPHA 2= beta 1= beta 2= beta 3=

• alpha 1 fight or flight, vasoconstricts smooth muscle, increase contractility, excititory
• alpha 2 inhibitory , vasodilate vessels, lower Bp, lower HR -beta1- excititory, increase contractility and HR, increase conduction velocity through epi -beta 2- inhibitory, decrase HR vasodilates once epi is released beta 3- works on adipose tissue, stilulates release of lipids into blood stream give atropine to increase HR, tx brady GI tract sympathetic decreased motility, secretions, and opens sphincters cosntipation The action potential is consistent as doesnt vary based on the amount of depolarization. The intensity of the signal conveyed in not by changing the AP but by increasing the ____________ of the action potential?

frequency Increasing the frequency of an AP potential can be altered by changing the _____________ which can occur in some demylenating diseases? conduction velocity change the intensity of the AP by increasing frequency once an AP reaches the ______________, a series of events leads to the release of neurotransmitters which will diffuse across the synapse to bind the next neuron or affector such as ___________ and glands? axon terminal muscle _________________ system is responsible for conscious thought, actions and unconscious regulation of homeostatis? a. central nervous system b. peripheral nervous system a. central nervous system The peripheral nervous system includes cranial nerves and which of the following? a. voluntary peripheral nerves (somatic) b. unvoluntary peripheral nerves (autonomic) c. Unconscious regulatory motor neurons (autonomic) d. unconscious regulatory motor neurons (somatic) a. voluntary peripheral nerves (somatic) c. unconscious regulatory motor neurons (autonomic) pheochromocytomas are tumors of the_____________ that release norepi/epi which causes an increase in _________, contractility, ______________ vascular resistance, and Bp. adrenal medulla increase HR epi vasocontricts which will increase Bp by tightening walls of smaller arteries and veins. works on adrenergic receptors help increaese Bp _____________ blockers affect the vascular smooth muscle (except in the heart) and help to reduce peripheral resistance Alpha 2 blockers (vasodilate, which lowers Bp) reduces peripheral resistance prevent stimulation of adrenergic receptors flomax-targets urinary tract specifically 1.doxazosin 2.prazosin 3.terazosin these arent first line but used in conjunction with others when Bp is hard to control

Beta blockers are given later if high levels of epi continue causing high _________- and _________________. Beta blockers decrease these effects through the beta 1 receptors found in HR and Contractility work on the Beta adrenergic receptor Beta-1 receptors , along with beta -2, alpha- 1 , and alpha-2 receptors , are adrenergic receptors primarily responsible for signaling in the sympathetic nervous system. Beta -agonists bind to the beta receptors on various tissues throughout the body. Beta-1 receptors are predominantly found in three locations: the heart, the kidney, and the fat cells Beta 1 receptor affect?