This activity contains 50 questions. Which part of the nervous system performs the higher-order thinking required to complete this practice exam? autonomic nervous system afferent division central nervous system peripheral nervous system Which of the following structures would not be part of the PNS? a ganglion an interneuron within the spinal cord a sensory receptor an interneuron within an autonomic ganglion The primary function(s) of the nervous system include: providing sensation of the internal and external environments integrating sensory information regulating and controlling peripheral structures and systems all of the above Neurons are responsible for: controlling the interstitial environment performing repairs in damaged neural tissue creating a three-dimensional framework for the CNS information transfer and processing in the nervous system The region of a neuron with voltage-gated sodium channels is the: perikaryon dendrite axon hillock soma Neurons are classified on the basis of their structure as: efferent, afferent, association, interneurons anaxonic, unipolar, bipolar, multipolar astrocytes, oligodendrocytes, microglia, ependymal motor, sensory, association, interneurons Neurons are classified on the basis of their function as: motor, sensory, association unipolar, bipolar, multipolar central, peripheral, somatic somatic, visceral, autonomic The two major cell populations of neural tissue are: satellite cells and Schwann cells neurons and neuroglia astrocytes and oligodendrocytes microglia and ependymal cells Which of the following CNS glial cells removes debris, wastes, and pathogens by phagocytosis? microglia astrocytes Schwann cells ependymal cells The white matter of the CNS represents a region dominated by the presence of: unmyelinated axons oligodendrocytes neuroglia astrocytes Depolarization of the membrane will shift the membrane potential toward: –90 mV –70 mV 0 mV –85 mV What is the term given to describe a shift in transmembrane potential from –70 mV to –90 mV? depolarization hyperpolarization repolarization none of the above If resting membrane potential is –70 mV and the threshold is –60 mV, a membrane potential of –62 mV will: produce an action potential repolarize the membrane to –80 mV depolarize the membrane to 0 mV not produce an action potential At the site of an action potential, the membrane contains: an equal amount of positive and negative ions on either side of the membrane an equal amount of positive ions on either side of the membrane an excess of positive ions inside and an excess of negative ions outside an excess of negative ions inside and an excess of negative ions outside Which of the following statements about repolarization of an axon is false? During repolarization, the axon will be in a refractory period. It is marked by the movement of potassium ions out of the cell membrane. It occurs when sodium ion channels are open. It follows depolarization of the axon. A node along the axon represents an area where there is: interwoven layers of myelin and protein a gap in the cell membrane an absence of myelin a layer of fat Nerve cell bodies in the PNS are clustered together in masses called: neuromodulators nodes ganglia proprioceptors The most important factors that determine the rate of action potential conduction are: the number of neurons and the length of their axons the strength of the stimulus and the rate at which the stimulus is applied the presence or absence of a myelin sheath and the diameter of the axon all of the above At an electrical synapse, the presynaptic and postsynaptic membranes are locked together at: synaptic vesicles neuromuscular junctions myelinated axons gap junctions Exocytosis and the release of acetylcholine into the synaptic cleft is triggered by: calcium ions leaving the cytoplasm calcium ions flooding into the axoplasm active transport of calcium into synaptic vesicles reabsorption of calcium into the endoplasmic reticulum Inhibitory or hyperpolarizing CNS neurotransmitters include: substance P and endorphins acetylcholine and norepinephrine dopamine and serotonin glutamate and aspartate An excitatory postsynaptic potential (EPSP) is: an action potential complying with the all-or-none principle a result of a stimulus strong enough to produce threshold a depolarization produced by the arrival of a neurotransmitter the same as a nerve impulse along an axon An inhibitory postsynaptic potential (IPSP) is a: depolarization produced by the effect of a neurotransmitter transient hyperpolarization of the postsynaptic membrane reflection of the activation of an opposing transmembrane potential repolarization produced by the addition of multiple stimuli Rabies is a viral disease contracted from the bite of an infected animal. Rabies bypasses many immune system defenses by traveling in peripheral neurons to reach the CNS. Which method of transport is not used by rabies use to reach the CNS? anterograde flow axoplasmic transport retrograde flow The reason that active neurons need ATP is to support: the synthesis, release, and recycling of neurotransmitter molecules the recovery from action potentials the movement of materials to and from the soma via axoplasmic flow all of the above Sensory neurons are responsible for carrying impulses: to the CNS away from the CNS to the PNS from the CNS to the PNS Interneurons, or associated neurons, differ from sensory and motor neurons because of their: inability to generate action potentials functional capabilities exclusive location in the brain and spinal cord structural characteristics Efferent pathways consist of axons that carry impulses: away from the CNS from the PNS to the CNS to the spinal cord and into the brain toward the CNS Graded potentials that develop on the postsynaptic membrane in response to a neurotransmitter are: presynaptic inhibitors presynaptic potentials presynaptic facilitators postsynaptic potentials The addition of stimuli occurring in rapid succession is: the absolute refractory period spatial summation facilitation temporal summation When sensory information is relayed from one processing center to another in the brain, the pattern is called: convergence divergence serial processing reverberation Interneurons are responsible for: collecting information from the external or internal environment carrying instructions from the CNS to peripheral effectors delivery of information to the CNS analysis of sensory inputs and coordination of motor outputs Sensory (ascending) pathways distribute information: from the central nervous system to the peripheral nervous system from processing centers in the brain to peripheral receptors from motor pathways to interneurons in the CNS from peripheral receptors to processing centers in the brain Tyson decides to travel overseas but does not have all the required vaccines needed before he goes. While on his trip, he contracts diphtheria. Which type of glial cell is particularly at risk from this disease? microglia Schwann cells satellite cells oligodendrocytes Schwann cells are glial cells responsible for: phagocytic activities in the neural tissue of the PNS surrounding nerve cell bodies in peripheral ganglia producing a complete neurilemma around peripheral axons secretion of cerebrospinal fluid When a barrier prevents the movement of opposite charges toward one another, a(n): generation potential is produced action potential occurs current is produced potential difference exists Which of the following statements about the sodium-potassium pump is correct? The sodium-potassium pump requires ATP to pump sodium and potassium ions from higher to lower concentrations along their concentration gradients. The sodium-potassium pump brings sodium into a neuron during depolarization and forces potassium out of a neuron during depolarization. The sodium-potassium pump is a leak channel that allows passive movement of sodium and potassium ions down the concentration gradient. The sodium-potassium pump's activity is needed after every action potential to restore resting potential. Which of the following is a correct statement of the all-or-nothing principle? A given stimulus either triggers a typical action potential or does not produce one at all. Action potentials occur in all neurons if a stimulus is applied that lowers the membrane potential. When a stimulus is applied it triggers an action potential in the membrane. A hyperpolarized membrane always results in the production of an action potential. During the relative refractory period, a larger-than-normal depolarizing stimulus can: cause the membrane to hyperpolarize bring the membrane to threshold and initiate a second action potential cause a membrane to reject a response to further stimulation inhibit the production of an action potential Saltatory conduction conducts impulses along an axon: at a velocity determined by the rate at which the stimulus is applied five to seven times faster than continuous conduction at a rate determined by the strength of the stimulus two to three times more slowly than continuous conduction In type C fibers action potentials are conducted at speeds of approximately: 500 mph 40 mph 150 mph 2 mph The larger the diameter of the axon, the: slower the rate of transmission size of the axon does not affect the rate of transmission or resistance faster the rate of transmission greater the resistance Facilitation in the neuron's transmembrane potential toward threshold refers to: any shift that makes the cell more sensitive to further stimulation repolarization produced by the addition of multiple stimuli transient hyperpolarization of a postsynaptic membrane all of the above Rachel decides to go swimming, but when she sticks her big toe into the water, she changes her mind because the water is too cold. The sensory neurons responsible for sending the message about the cold water temperature are: interoceptors enviroceptors exteroceptors proprioceptors The main functional difference between the autonomic nervous system and the somatic nervous system is that the activities of the ANS are: primarily voluntary controlled involved with carrying impulses to the CNS involved with affecting skeletal muscle activity primarily involuntary or under "automatic" control Lulu, who is 50 years old, decides she wants to receive Botox treatments. If Botox, short for botulism toxin, prevents the release of ACh from synaptic terminals, what effect should Lulu expect from having Botox injected into her facial muscles? difficulty breathing temporary paralysis in the injected facial muscles prolonged muscle contractions in her facial muscles none of the above Reverberation in neural circuits refers to collateral axons that: synapse on the same postsynaptic neuron use positive feedback to simulate presynaptic neurons involve several neuronal pools processing the same information at one time relay sensory information from one processing center to another in the brain Emma is very excited because after taking up running several months ago, she has begun to experience the phenomenon called "runners high." This is caused by the production of endorphins. What is the effect of the endorphins on Emma when she runs? Endorphins are blocking the transmission of substance P, a neurotransmitter that sends information about pain to the CNS. Endorphins cause an increase in the amount of myelin on axons, making impulses travel faster. Endorphins lower the level of threshold at the initial segments of her axons, making it easier for impulses to be transmitted through her body. None of the above. Which of the following is the most excitatory neurotransmitter in the brain and functions in learning and memory? glutamate dynorphins norepinephrine anamidine Ann and Elise are two college students on an overseas vacation. Because they both love seafood, they stop at a restaurant in a coastal town for lunch. After dining on shellfish, they become very sick and have trouble breathing. What may have happened to Ann and Elise? They may have consumed ciguatoxin (CTX), which can interfere with muscle control. They may have consumed some tetrodotoxin (TTX), which can cause abnormal sensations. They may have consumed saxitoxin (STX), which blocks sodium ion channels. Any of the above could be correct. TTX, STX, and CTX all block sodium ion channels, cause abnormal sensations, and interfere with muscle control. Match the following: Match the following terms with their correct definitions: Using the pull-down menus, match each item in the left column to the corresponding item in the right column. 1.1 CNS 1.2 ANS A component of the efferent division of the nervous system, this group of cells provides automatic regulation of smooth muscle, cardiac muscle, and glandular secretions at a subconscious level. This location-based division of the nervous system contains the brain and spinal cord. 1.3 Afferent division This location-based division of the nervous system includes all the neural tissue found outside the CNS. This functional division of the PNS includes neural tissues carrying somatic and motor commands out of the CNS to muscles and glands. 1.4 PNS This functional division of the PNS includes cells bringing sensory information to the CNS from receptors in peripheral tissues and organs. 1.5 Efferent division Match the neuron components with their appropriate functions: Using the pull-down menus, match each item in the left column to the corresponding item in the right column. 2.1 Collaterals 2.2 Dendrites The end of axons and telodendria that often contain neurotransmitters used to communicate to other cells at a synapse Slender processes that extend from the cell body and are the structures used to transmit information into the cell body The cytoplasm around the nucleus containing neurofilaments and neurotubules 2.3 Perikaryon Branches of an axon that allow the neuron to communicate with numerous cells 2.4 Synaptic terminal Put the following steps in the generation of an action potential into the proper sequence from first (1) to last (6): Using the pull-down menus, match each item in the left column to the corresponding item in the right column. 3.1 1 3.2 2 All gated sodium channels close. Voltage-regulated sodium channels open. 3.3 3 3.4 4 Voltage-regulated potassium channels open. Repolarization begins. Transmembrane potential goes from –70 mV to +30 mV. 3.5 5 Graded depolarization brings membrane area to threshold. 3.6 6 Match the specific molecule to the major neurotransmitter classes: Using the pull-down menus, match each item in the left column to the corresponding item in the right column. 4.1 GABA Dissolved gases 4.2 Norepinephrine Biogenic amines Amino acids 4.3 Nitric oxide (NO) Neuropeptides 4.4 Opioids (endorphins) Put in correct order the steps that describe the function of a cholinergic synapse: Using the pull-down menus, match each item in the left column to the corresponding item in the right column. 5.1 1 An action potential arrives and depolarizes the synaptic knob. 5.2 2 5.3 3 Acetylcholine is removed by acetylcholinesterase. Postsynaptic neuron is depolarized. ACh binds to receptors on the postsynaptic neuron. 5.4 4 Calcium enters the presynaptic neuron, triggering the exocytosis of ACh. Extracellular calcium enters the synaptic cleft. 5.5 5 5.6 6 The ependymal cells line the blood vessels that supply the neural tissues of the brain, thereby forming the blood-brain barrier True False Neurotransmitters that depress the resting potential are called excitatory. True False The all-or-none principle applies to excitable membranes, such as neuron membranes. This principle states that either a stimulus is great enough to depolarize a membrane to threshold and thus trigger an action potential, or the stimulus is not able to depolarize to threshold and thus an action potential does not occur. True False Unipolar neurons have only one cell process, the axon. True False Acetylcholine is broken down in the mitochondrion by acetylcholinesterase. True False This activity contains 5 questions. Amy wants to text-message her friend Michelle. Amy sends impulses from her brain to the skeletal muscles in her arms and hands, enabling her to correctly punch the buttons on her phone to create the text message. What type of axon fibers is Amy using to send these messages to her brain? The separation of positive and negative charges by the cell membrane provides a resistance since it keeps the charges from diffusing to equilibrium; if the charges are able to move in response to voltage, that movement is called a(n) . Neurons have high amounts of sodium ions and chlorine ions in their extracellular fluid (ECF), while the intracellular fluid contains high levels of negatively charged proteins. ions and A chemical synapse at which the neurotransmitter is acetylcholine is called a(n) synapse. A neurotransmitter is received at a postsynaptic cell, and rather than raising the membrane potential from –70 mV, it is instead lowering the potential to –80 mV. Does the interaction of neurotransmitter and receptor produce an excitatory or inhibitory response? Correctly label the parts of the adult spinal cord. For each item below, use the pull-down menu to select the letter that labels the correct part of the image. 1.1 thoracic spinal nerves 1.2 conus medullaris 1.3 filum terminale 1.4 cervical enlargement 1.5 cauda equina Match the labels to the correct parts of the sectional view of the spinal cord. For each item below, use the pull-down menu to select the letter that labels the correct part of the image. 2.1 ventral root 2.2 posterior gray horn 2.3 lateral gray horn 2.4 Posterior median sulcus 2.5 anterior median fissure 2.6 dorsal root ganglion Correctly match each label to the appropriate step in a reflex arc. For each item below, use the pull-down menu to select the letter that labels the correct part of the image. 3.1 information processing in the CNS C 3.2 activation of motor neuron D 3.3 response by effector E 3.4 activation of sensory neuron B 3.5 arrival of stimulus and activation of receptor A This activity contains 5 questions. Put the following steps in a neural reflex arc into the proper order from first (1) to last (5): Using the pull-down menus, match each item in the left column to the corresponding item in the right column. 1.1 1 Information processing 1.2 2 Activation of a receptor by a stimulus 1.3 3 Activation of a sensory neuron Activation of a motor neuron 1.4 4 Response by a peripheral effector 1.5 5 Match the following terms to the appropriate definition: Using the pull-down menus, match each item in the left column to the corresponding item in the right column. 2.1 Neural center 2.2 CNS nucleus A collection of neuron cell bodies with a common function Delivering information from the CNS motor control centers to the effecter organs Portions of the brain surface covered by a thick layer of gray matter 2.3 Neural cortex 2.4 Tract Conducts information from peripheral receptors to processing centers in the brain A collection of neuron cell bodies with a common function and a discrete anatomical boundary 2.5 Sensory pathways Bundles of axons in the CNS that share common origins, destinations, and functions 2.6 Motor pathways Match each term with the function associated with it: Using the pull-down menus, match each item in the left column to the corresponding item in the right column. 3.1 Sensory nuclei 3.2 Motor nuclei 3.3 Posterior gray horns Somatic and visceral sensory nuclei Relay information from one side of the spinal cord to the other before reaching its destination in the gray matter Issue motor commands to peripheral effectors 3.4 Gray commissures White matter that carries information toward the brain White matter that carries motor information to the spinal cord 3.5 Ascending tracts 3.6 Descending tracts Receive and relay sensory information from peripheral receptors Match each spinal nerve to the plexus to which it belongs: Using the pull-down menus, match each item in the left column to the corresponding item in the right column. 4.1 Genitofemoral nerve Lumbar plexus 4.2 Phrenic nerve Brachial plexus Cervical plexus 4.3 Ulnar nerve Sacral plexus 4.4 Sciatic nerve Match the reflexes with their correct descriptions: Using the pull-down menus, match each item in the left column to the corresponding item in the right column. 5.1 Tendon reflex A polysynaptic reflex in which the motor response occurs on the side opposite the stimulus 5.2 Flexor reflex 5.3 Stretch reflex 5.4 Crossed extensor reflex A form of withdrawal reflex in which the muscles of a limb contract to move the limb away from a source of stimulation Monitors external tension produced during a muscular contraction and prevents tearing or breaking of the tendon A monosynaptic reflex that prevents excessive stretching of skeletal muscles This activity contains 5 questions. The outermost spinal meninx is the thin layer that uses the denticulate ligaments to stabilize the position of the spinal cord. True False The brachial plexus is found in the lower back. True False The cauda equina is composed of the long ventral and dorsal roots of spinal segments L2 to S5. True False A sensory message entering the spinal cord enters the dorsal side of the spinal cord, while the motor response exits the ventral side. True False A positive Babinski reflex is normal in an infant. True False This activity contains 5 questions. There are three complex, interwoven networks of compound nerve trunks called plexuses that branch into peripheral nerves; in descending order, these are the cervical plexus, the brachial plexus, and the plexus. The largest nerve in the body is the sciatic nerve, which arises from the plexus. The reflex, a representative withdrawal reflex, is used to move a limb away from a stimulus. The best-known example of a monosynaptic reflex is the The withdrawal of CSF from the subarachnoid space is a called a (Answer is two words.) reflex. .