Nervous system 1
What type of nerves are found in the dorsal root? A. only afferent nerves B. only efferent nerves C. both afferent and efferent nerves D. only ganglionic nerves
Answer is A: Afferent (or sensory) nerves/neurons are in the dorsal root of the spinal nerves.
What is the function of the corpus callosum? A. connects two cerebral hemispheres B. connects cerebellum to midbrain C. connects areas within same hemisphere D. it is a relay centre
Answer is A: Commissural fi bres pass through the corpus callosum that con-nect corresponding areas in the 2 hemispheres
Which one of the following is NOT a function of the cerebral spinal fl uid? A. to produce hormones B. to transport nutrients around the brain C. to protect the spinal cord D. to cushion the brain
Answer is A: The CSF does not produce hormones.
An epidural block involves injecting anaesthetic into the epidural space. What is the main reason for this? A. Anaesthetic in this space only affects spinal nerves in the immediate vicin-ity of the injection. B. The anaesthetic will be readily distributed along the spinal cord by the cere-bral spinal fl uid from this space. C. There is less chance of damaging the spinal cord when inserting the needle into this space. D. The epidural space is highly vascularised and so will the anaesthetic will be quickly absorbed.
Answer is A: The epidural space contains adipose tissue and spinal nerves pass through this space. Injecting anaesthetic into this space anaesthetises (blocks), the nearby spinal nerves.
With respect to the spinal cord, where is the epidural space? A. external to the dura mater B. between the arachnoid and pia maters C. between the arachnoid and dura maters D. between the two layers of the dura
Answer is A: The epidural space is above or on top of the dura and external to the spinal cord. It is between the spinal cord and the surrounding vertebrae.
What is found in the epidural space? A. adipose tissue B. venous sinuses C. choroid plexus D. cerebrospinal fl uid
Answer is A: The epidural space is on top of (or outside of) the dura mater. It is the space between the spinal cord and the vertebrae. It contains adipose tissue.
One of the functions of the prefrontal cortex is: A. making conscious decisions B. controlling motor functions C. detecting and integrating sensory information D. enabling word recognition
Answer is A: The pre-frontal cortex (of frontal lobe) performs abstract intel-lectual functions such as predicting the consequences of actions or events. Hence it helps us make conscious decisions.
In the spinal cord, the ascending tracts contain A. white matter and transmit sensory information B. white matter and transmit motor commands C. gray matter and transmit sensory information D. gray matter and transmit motor commands
Answer is A: The term "ascending" means travelling upwards to the brain. Hence this must be sensory information from the body. The tracts are white as they are myelinated which gives the nerves a white appearance.
Which of the following is NOT a meninge? A. cerebra mater B. pia mater C. dura mater D. arachnoid mater
Answer is A: This choice is nonsense
The precentral gyrus is the area of brain which houses A. the primary motor cortex B. our association areas C. the primary somatosensory area D. our higher intellectual functions
Answer is A: This gyrus (outfold) is immediately anterior to the central sulcus (infold).
In a cross-section view of the spinal cord, there is a butterfl y-shaped structure. What would the posterior gray horn of this structure primarily consist of? A. the axons of motor neurons B. the cell bodies of interneurons C. the cell bodies of motor neurons D. the cell bodies of sensory neurons
Answer is B: .The posterior (or dorsal) gray horn contains interneurons that receive stimuli from sensory axons (whose cell bodies reside in the dorsal root ganglion).
What is the most superfi cial part of the brain called? A. diencephalon B. cerebral cortex C. cerebellum D. mesencephalon
Answer is B: Each hemisphere has a superfi cial layer of "gray matter" called the cerebral cortex, lying over "white matter".
What is the role of the hypothalamus? A. it receives sensory input and relays it to the cerebral cortex B. it is the autonomic control centre which directs the function of the lower CNS C. it uses past experience to analyse and act on sensory input D. it integrates sensory information from association areas and performs abstract intellectual functions
Answer is B: Hypothalamus is the main visceral control centre of body homeo-stasis. It is the autonomic control centre from which orders fl ow to lower CNS centres for execution.
Which best describes the function of the association area of the temporal lobe? A. It perceives of movement B. It interprets the meaning of sound patterns C. It recognises of geometric shapes and faces D. It perceives meaningful information from different senses
Answer is B: The temporal lobe contains the auditory cortex. It interprets sound from the hearing mechanism in the adjacent ears.
What does the term 'decussation' mean and where does it occur? A. decussation = span. It occurs between the superior part of the brain and the inferior B. decussation = cross. It occurs between the anterior part of the brain and the posterior C. decussation = cross over. It occurs between the pons and the spinal cord D. decussation = associate. It occurs between the sensory area and the sensory association area
Answer is C: A decussation is a crossing over. Nerves from the left side of the brain cross over to the right side of the spinal cord to innervate the right hand side of the body (and vice versa)
If a person had a pre-frontal lobotomy what would be the physiological consequences? A. Movement would be impaired B. Sensory function would be impaired C. The ability to assess the consequence of actions would be impaired D. Speech would be impaired
Answer is C: If the connection between the pre-frontal cortex and the brain is severed, the person would not have anxiety, tension or frustration, or tact and decorum. They would be unaware of the consequences of their actions.
The central sulcus separates gyri involved with which two major functions? A. vision and taste B. vision and hearing C. motor and sensory D. emotion and memory
Answer is C: Motor function resides in the pre-central gyrus, while sensory function resides in the post-central gyrus.
What is the blood-brain barrier? An adaptation of the capillaries serving the brain that: A. prevents fat-soluble molecules from entering the brain. B. inhibits all substances from passing from the blood stream into the brain C. selectively inhibits many substances from passing from the blood stream into the brain D. operates from birth to prevent foreign molecules entering the brain.
Answer is C: The BBB is a selectively permeable barrier to many water soluble particles that is incomplete at birth.
What do neurones in the pre-central gyrus do? A. they receive information from general sense receptors in muscle and skin B. they communicate with motor, sensory and multi-modal association areas C. they allow conscious control of skilled voluntary muscle movements D. they process and relay auditory and visual input
Answer is C: The pre-central gyrus is the primary motor area. It allows con-scious control over skeletal muscle movement.
The blood brain barrier functions to protect the brain from A. lipid soluble drugs, alcohol and nicotine B . fl uctuations in oxygen and carbon dioxide concentrations C. neurotransmitters, bacteria and neurotoxins D. dehydration and fl uctuating blood glucose level
Answer is C: These substances would alter the function of, or damage the brain. Glucose, oxygen, carbon dioxide, ethyl alcohol and nicotine can cross the BBB easily.
An image of the cross-section of a spinal cord would show "anterior (or ventral) horns". What is in that region? A. spinal nerves B. ascending tracts C. cell bodies of motor neurons D. white matter
Answer is C: the "horns" contain gray matter which is the cell bodies of motor neurons. The dorsal horns contain sensory nuclei (cell bodies of neurons)
What is found between the arachnoid and pia mater? A. adipose tissue B. venous sinuses C. choroid plexus D. cerebrospinal fluid
Answer is D: Between the arachnoid and pia mater is the sub-arachnoid space and this is fi lled with cerebrospinal fl uid.
Which part of the brain controls breathing, heart function, vasoconstriction and swallowing? A. mesencephalon B. cerebellum C. diencephalon D. brainstem
Answer is D: Centres in brainstem produce the rigidly programmed, automatic behaviours necessary for survival e.g. respiratory centre (breathing rhythm), cardiovascular centre (force & rate of heart contraction, vasoconstriction), vomiting, coughing, hiccoughing, swallowing). The mesencephalon is part of the brainstem.
Which of the following statements about the blood-brain barrier is TRUE? It A. consists of the meninges which surround the brain B. is a protective mechanism which limits entry of alcohol into the brain C. is poorly developed in the newborn who are therefore less sensitive to drugs which act on the brain D. is unable to prevent entry of lipid-soluble toxins into the brain
Answer is D: The BBB does not prevent lipid-soluble toxins, such as alcohol and nicotine, from entering the brain.
The central sulcus of the brain lies between which two lobes? A. parietal and occipital B. temporal and occipital C. frontal and temporal D. frontal and parietal
Answer is D: The central sulcus separates the frontal lobe from the left and right parietal lobes.
What is the purpose of inserting a needle into the epidural space? It: A. Allows access to the cerebro-spinal fl uid B. Enables the cerebro-spinal fl uid pressure to be measured C. Enables permanent drainage of cerebro-spinal fl uid to treat hydrocephalus D. Allows access to administer analgesia and anaesthesia
Answer is D: The epidural space is on the outside of the spinal cord, hence does not contain CSF. It is into this space that the analgesia for a spinal block is injected.
In what respect does "gray matter" differ from "white matter" A. gray matter refers to the CNS while white matter refers to the PNS. B. white matter makes up the autonomic nervous system, gray matter does not. C. gray matter is found in the cerebrum, while white matter occurs in the cer-ebellum and the diencephalon. D. gray matter contains the cell bodies of nerve cells white matter contains axons.
Answer is D: The myelin that surrounds the axons of neurons gives them a white appearance.
If a person suffers a stroke and damage occurs to the occipital lobe of the brain which function is the most likely to be affected? A. the ability to write B. speech C. hearing D. vision
Answer is D: The occipital lobe contains the visual cortex (processes visual information) and the visual association area (interpretation of images). Hence damage to the occipital lobe would affect vision.
What is the function of the thalamus? A. connects two cerebral hemispheres B. connects cerebellum to midbrain C. connects areas within same hemisphere D. it is a relay centre
Answer is D: The thalamus is about 13 "nuclei" that receive then distribute (that is, relays) sensory information from the body to the cerebral cortex and basal nuclei.
Spinal nerves are formed from a dorsal root and a ventral root. What is true of the ventral root? A. they contain sensory neurons carrying afferent impulses B. they contain sensory neurons carrying efferent impulses C. they contain motor neurons carrying afferent impulses D. they contain motor neurons carrying efferent impulses
Answer is D: The ventral root contains axons of motor neurons. That is, they carry motor information from the brain to the body - this is efferent (outgoing) information.
Where are the cell bodies of somatic motor neurones found? A. in the peripheral nervous system B. in the central nervous system C. in the dorsal root ganglia D. in the spinal cord
Answer is D: They are found in the spinal cord (in the ventral gray horns). Choice B is also correct, but choice D is more specifi c. The dorsal root ganglia contain cell bodies of sensory neurons).
What is the name of the nerve cell structure that carries incoming impulses towards the cell? A. dendrite B. axon C. cell body D. ganglion
Answer is A: Dendrites receive incoming (efferent or stimulating) impulses.
Which of the following is NOT composed of "gray matter"? A. spinothalamic tract B. cerebral cortex C. basal nuclei D. post-central gyrus
Answer is A: Gray matter refers to cell bodies of neurons while white matter is aggregations of myelinated axons. The spinothalamic "tract" is a bundle of nerves (axons) carrying information to the brain.
Which of the following statements about the blood-brain barrier (BBB) is correct? A. The BBB prevents fluctuations of hormone and ion concentrations in blood from affecting the brain. B. It is formed by Schwann cells wrapping around capillaries. C. The brain is supported by (it fl oats in) the BBB. D. The BBB is formed by the choroid plexus.
Answer is A: Hormones and ions cannot pass through the BBB. (It is astro-cytes, not Schwann cells that from part of the BBB; the brain fl oats on CSF; CSF is formed by the choroid plexus).
Cortico-spinal pathways cross-over from one side of the brain to the other side. Where does this cross-over occur? A. In the medulla oblongata B. In the cerebellum C. In the hypothalamus D. In the reticular formation
Answer is A: In the medulla oblongata at the "decussation of pyramids".
A multipolar neuron has more than one what? A. dendrite attached to the cell body B. axon attached to the cell body C. synaptic terminal attached to the axon D. cell body
Answer is A: Many dendrites are attached to the cell body of multipolar neurones
What are the major type of nerve cells in the CNS? A. multipolar B. sensory C. interneurons D. unipolar
Answer is A: Multipolar are most common in the CNS. Motor neurons, whose cell bodies lie within the spinal cord, are multipolar.
Which of the following would conduct an action potential with the greatest speed? A. myelinated, large diameter fibres B. myelinated, small diameter fibres C. unmyelinated, large diameter fi bres D. unmyelinated, small diameter fi bres
Answer is A: Myelinated fibres allow for faster conduction speed as does greater diameter of axon.
What name is used for a nerve cell? A. neuron B. neuroglia C. ganglion D. astrocyte
Answer is A: Neurons (or neurones) are nerve cells. Neuroglia are cells in the nervous system but they do not produce nerve impulses.
What part of the brain subconsciously provides the appropriate pattern of smooth co-ordinated skeletal muscle contraction for movements that we have learned? A. the cerebellum B. the brainstem C. the cerebrum D. the diencephalon
Answer is A: Subconscious coordination of learned (and practised) movements is done by the cerebellum.
What is the last part of a nerve cell that is involved when a nerve impulse passes to another cell? A. synaptic knob B. axon hillock C. dendrite D. axon
Answer is A: Synaptic knobs are at the distal end of an axon. The axon hillock is at the proximal end.
Which of the following substances CANNOT cross the blood-brain barrier? A. metabolic wastes, toxins, K + B. O 2 , CO 2 and H 2 O C. fats, fatty acids, fat soluble substances D. alcohol, nicotine, anaesthetics
Answer is A: The BBB protects the brain from these substances. The sub-stances in the other choices can all cross the BBB.
What is an "action potential"? It is: A. when the resting potential changes from −70 mV to +30 mV and then back again. B. the name given to the difference in electrical charge between the inside and outside of the plasma membrane of a neurone. C. the name given to the stimulus that changes the resting potential from −70 to −50 mV. D. the voltage produced by a stimulus which causes a nerve impulse to be generated.
Answer is A: The action potential is the name given to the change in voltage of the inside of the cell from −70 to +30 and back to −70 mV again. This voltage change propagates along the axon.
Which four structures together make up the brain? A. cerebrum, diencephalon, brainstem and cerebellum B. cerebrum, thalamus, brainstem and cerebellum C. cerebrum, diencephalon, meninges and cerebellum D. spinal cord, diencephalon, brainstem and medulla oblongata
Answer is A: The brainstem is at the end of the spinal cord, just inferior to the diencephalon which is surrounded by the cerebrum. The cerebellum is dorsal to the brainstem and inferior to the cerebrum.
What part of the brain contains the motor areas and the sensory areas? A. cerebrum B. diencephalon C. brainstem D. cerebellum
Answer is A: The central sulcus of the cerebrum separates the gyri containing the primary motor area in the frontal lobe and the primary sensory areas in the parietal lobes.
Which layer of membrane around the brain is the most superficial? A. Dura mater B. Meningeal mater C. Arachnoid mater D. Pia mater
Answer is A: The dura mater is in contact with the skull.
Where does the spinal cord start and fi nish? A. It extends from the foramen magnum to L1 - L2 B. It extends from the foramen magnum to the sacrum C. It starts at the superior part of the medulla oblongata and extends to the inferior part of the cauda equina. D. It extends from C7 to L5
Answer is A: The foramen magnum is the hole in the occipital bone. Beyond L2, spinal nerves descend within the arachnoid mater but are not enclosed within the pia mater that covers the spinal cord.
Depolarisation of the cell membrane involves: A. sodium channels opening to allow Na + to flow in. B. potassium channels opening to allow K + to fl ow in. C. chloride pumps quickly pumping large amounts of Cl − outside. D. electrical attraction between K + inside and Cl − outside.
Answer is A: The infl ux of positive Na ions changes the polarisation of the cell from negative inside to positive inside at that location on the membrane. This reversal is called depolarisation.
In nerve fi bres with myelin sheaths, which of the following is true about the electrical conduction? A. It is 'saltatory', so propagates at higher speed B. It requires more energy to send an impulse C. The conduction between adjacent axons is enhanced ('cross talk' is increased) D. It is slower due to the separation between the 'nodes of Ranvier'
Answer is A: The myelin sheath increases the speed of conduction along an axon as the action potential is regenerated when migrating Na ions reach the next node. It "jumps" (saltates) from one node to the next.
What would happen if a neuron lost its myelin sheath? A. N a + would leak out of the axon leaving too few ions to stimulate the Na channels at the next node to open. B. The neuron would die. C. More Na + channels would be exposed allowing freer entry so conduction speed would increase. D. More K + channels would be exposed allowing freer exit so the cell would hyperpolarise.
Answer is A: The myelin sheath prevents sodium ions from leaking back into the intracellular fl uid hence they can travel with minimum diminution to the next node to trigger the opening of abundant voltage-gated sodium channels.
There is a space between a neuron and the cell it stimulates, that is crossed by a neurotransmitter. What is it called? A. synaptic cleft B. voltage-gated channel C. synapse D. post-synaptic membrane
Answer is A: The synaptic cleft lies between the pre-synaptic membrane of the neuron and the post-synaptic membrane of the cell about to be stimulated.
In which part of the brain is the thalamus found? A. diencephalon B. cerebrum C. cerebellum D. brainstem
Answer is A: The thalamus, along with the hypothalamus, pituitary gland & pineal gland, form the diencephalon.
Which of the lists of structures include all of the central nervous system? A. cerebellum, cerebrum, spinal cord, diencephalon, brainstem B. midbrain, spinal cord, autonomic nerves, pons, diencephalon C. midbrain, cerebellum, special sense organs, medulla oblongata D. cerebrum, sensory neurons, motor neurons, cerebellum
Answer is A: There are five distinct structures in the CNS. Autonomic nerves, motor and sensory neurones and special sense organs are not part of the CNS.
What part of the brain contains the autonomic control centre whose orders reg-ulate food intake, water balance and body temperature? A. hypothalamus B. thalamus C. medulla oblongata D. cerebellum
Answer is A: These homeostatic roles are performed by the hypothalamus.
What are the "ascending tracts" of the spinal cord and what do they do? A. They are white matter and they transmit sensory information to the brain. B. They are gray matter and they transmit sensory information to the brain. C. They are white matter and they transmit motor information to the brain. D. They are gray matter and they transmit motor information to the brain.
Answer is A: Tracts means white matter as axons are myelinated which makes them look white. Ascending means that the nerve impulses are going from body to brain, that is they are carrying sensory input to the brain.
What term refers to the sudden movement of potassium ions across the cell membrane to the outside of a nerve cell? A. Repolarisation B. Depolarisation C. The action potential D. The potassium pump
Answer is A: When Na + ions move into the axon it is called depolarisation as the resting potential changes from −70 mV to + 30 mV. Movement out by K +ions is called repolarisation as the potential returns to −70 mV. One followed by the other is the action potential.
Which of the following CAN cross the blood-brain barrier to enter the brain? A . K + B. O 2 C. proteins D. most pharmaceuticals
Answer is B: All cells require oxygen, so of course it can cross the BBB. Most pharmaceuticals cannot.
What type of neurones are motor neurones? A. Anaxonic B. Multipolar C. Bipolar D. Unipolar
Answer is B: All motor neurones are multipolar.
One of the following is not a meninge. Which one? A. Pia mater B. Alma mater C. Arachnoid mater D. Dura mater
Answer is B: Alma mater is the university that you attended.
Which of the following is a true statement about an "action potential"? A. It refers to the movement of a neuro-transmitter along an axon. B. It travels away from the cell body along the axon. C. It causes K + to rush into the cell. D. It travels between the dendrite and the axon hillock.
Answer is B: An action potential is an efferent impulse that travels along the axon away from the cell body.
Which of the following statements about the action potential is FALSE ? A. The action potential lasts about four milliseconds. B. It is triggered by anions crossing the cell membrane. C. The sequence: 'Na ions moving in, K ions moving out' constitutes the action potential. D. Repolarisation follows depolarisation of the cell membrane.
Answer is B: Anions (+ve ions) crossing the membrane is the first part of the action potential, but this movement is triggered by a graded potential that is above threshold arriving at the start of the axon (the axon hillock). So choice D is false.
What is the primary function of the cerebellum? A. it regulates such things as body temperature, water balance and emotional responses B. it refi nes/adjusts learned motor movements so that they are performed smoothly. C. it controls our automatic functions such as breathing, digestion and cardio-vascular functions D. it is the origin of our conscious thoughts and intellectual functions
Answer is B: Cerebellum subconsciously provides precise timing and appropri-ate patterns of learned skilled skeletal muscle contraction for smooth coordi-nated movements, posture & agility.
What is the depolarisation and repolarisation of a nerve cell membrane called? A. graded potential B. action potential C. threshold potential D. resting membrane potential
Answer is B: Depolarisation of the resting membrane potential leads to an action potential.
Which is the major type of nerve cell in the CNS? A. Anaxonic B. Unipolar C. Bipolar D. Multipolar
Answer is D: Multipolar are most common in the CNS. Motor neurons, whose cell bodies lie within the spinal cord, are multipolar.
What is meant by an absolute refractory period? A. at least 5 ms must elapse from the time of the first action potential before a second can be initiated B. an action potential cannot be initiated during this period regardless of the strength of the stimulus C. an action potential can be initiated if the strength of the stimulus is higher than normal (>70 mV) D. an action potential can be initiated if the strength of the stimulus is lower than normal (<70 mV)
Answer is B: During the ~0.5 ms period of the action potential in which sodium ions are rushing into a nerve cell, the nerve cannot respond to any stimulus not matter how strong the stimulus. Because of the impossibility of response, this period is called "absolutely" refractive. (refractory = resisting ordinary methods).
Which nerve cells carry impulses from the brain to the muscles? A. Sensory B. Motor C. Afferent D. Association
Answer is B: Motor (or efferent) nerves carry impulses away from the CNS to the muscles.
Which word correctly completes the statement: "All motor neurons are..." A. interneurons B. multipolar C. bipolar D. unipolar
Answer is B: Motor neurones (that innervate muscles) are multipolar.
Which of the three structures listed below constitute a nerve cell? A. dendrites, ganglion, myelin sheath B. dendrites, cell body, axon C. neuron, neuroglia, synaptic process D. cell body, synaptic knobs, efferent fibre
Answer is B: Neuroglia and ganglion are not part of a neuron. Efferent fi bre is an ambiguous term that may refer to an axon or to a motor neuron.
When we say that the cell membrane is polarised we mean that A. the outside of the cell is negative with respect to the inside B. the inside of the cell is negative with respect to the outside C. there are more Na + ions and less K + ions inside the cell than outside. D. Na + ions have moved out of the cell and K + ions have moved in
Answer is B: Polarised means that the charge is different on the two sides of the membrane, with the inside being negative with respect to the outside
What is linked to the posterior gray horn of the spinal cord? A. the dorsal root of the spinal nerve that carries motor fi bres B. the dorsal root of the spinal nerve that carries sensory fi bres C. the ventral root of the spinal nerve that carries sensory fi bres D. the ventral root of the spinal nerve that carries motor fi bres
Answer is B: Posterior means dorsal. The dorsal root carries axons of sensory neurons.
In the peripheral nervous system, which cells form the myelin sheath? A. Ependymal cells B. Schwann cells C. Astrocytes D. Oligodendrocytes
Answer is B: Schwann cells surround the axon to form the myelin sheath in peripheral neurones. Oligodendrocytes perform a similar function for neurones in the CNS.
What is the name of the lobe of the brain that is immediately superior to the cerebellum? A. dorsal B. occipital C. posterior D. parietal
Answer is B: The cerebellum nestles into the cerebrum immediately inferior to the occipital lobe.
Which of the following structures together make up the brainstem? A. medulla oblongata, pons, midbrain, cerebellum B. medulla oblongata, pons, midbrain C. medulla oblongata, pons, midbrain, thalamus D. medulla oblongata, pons, midbrain, pineal gland
Answer is B: The cerebellum, thalamus and pineal gland are not part of the brainstem.
What part of the brain contains the main visceral control centre of body homeostasis? A. cerebrum B. diencephalon C. brainstem D. cerebellum
Answer is B: The hypothalamus of the diencephalon
In what part of the brain is the "decussation of the pyramids" found A. pons B. medulla oblongata C. midbrain D. hypothalamus
Answer is B: The medulla oblongata is where the pyramidal tracts crossover (decussate).
Which glial cells are responsible for forming the myelin sheath around periph-eral nerve cells? A. Astrocytes B. Schwann cells C. Satellite cells D. Oligodendrocytes
Answer is B: The oligodendrocytes perform a similar function for neurones within the CNS.
Which of the following statements is INCORRECT ? A. The pituitary gland dangles from the hypothalamus by the infundibulum B. The post-central gyrus houses the primary motor cortex C. The thalamus surrounds the third ventricle D. White matter consists of myelinated axons of neurons
Answer is B: The post-central gyrus houses the primary sensory cortex (not motor)
Which of the following roles is NOT performed by the hypothalamus? A. autonomic control of heat activity and blood pressure B. relaying visual and auditory information to the cerebral cortex C. production of hormones for the posterior pituitary D. body temperature regulation
Answer is B: The thalamus relays visual and auditory information, not the hypothalamus.
To what does the "blood-brain barrier" refer? A. the three meninges that surround the brain and spinal cord. B. the tight junctions between endothelial cells of the capillaries that serve the brain. C. the structures that prevent fat-soluble molecules from entering the brain from the blood. D. the structure that produces cerebrospinal fl uid from blood.
Answer is B: This answer is not a complete description of the BBB as it does not include astrocytes, but it is the best of the four choices.
What do the descending tracts of the spinal cord contain? A. white matter and transmit sensory information B. white matter and transmit motor commands C. gray matter and transmit sensory information D. gray matter and transmit motor commands
Answer is B: Tracts refers to axons which are encased in myelin which makes them look white. Descending refers to impulses that carry information from the brain to the body (motor commands) usually to muscle.
What is the effect of the movement of Na + into a nerve cell followed very soon by the movement of K + out of the nerve cell? A. this establishes the resting membrane potential B. these movements are known as depolarisation and repolarisation C. these movements repolarise the cell D. it changes the membrane potential from about −70 mV to about −50 mV
Answer is B: When Na + moves into a nerve cell the cell depolarises (from −70 mV to about +30 mV) when soon afterwards K + moves out of the nerve cell, it repolarises (from +30 mV back to −70 mV).
Complete the sentence. Neuroglia A. are bundles of axons B. contain cell bodies outside the central nervous system C. are a type of neuron D. include ependymal cells, astrocytes and satellite cells
Answer is D: Neuroglia are nervous system cells that are not neurons. Choice D gives three types of these cells.
Which of the following lists all of the main sections of the brain? A. cerebrum, brainstem, midbrain, medulla oblongata B. cerebrum, cerebral cortex, cerebellum, mesencephalon C. cerebellum, diencephalon, brainstem, cerebrum D. cerebral cortex, midbrain, diencephalon, cerebellum
Answer is C: Apart from the two "cere" (cerebrum & cerebellum), diencepha-lon and brainstem must be included.
What feature do the dendrites of a nerve cell have? A. they transmit an action potential B. they contain the cell nucleus and organelles C. they carry incoming impulses to the cell body D. they are connected to the cell body by the axon hillock
Answer is C: Dendrites are the afferent pathway by which a stimulus is brought to a cell body.
Which structure carries incoming impulses towards the nerve cell body? A. axon hillock B. axon C. dendrite D. synaptic knobs
Answer is C: Dendrites receive stimuli for nerve cells and transmit them towards the cell body. An axon transmits a nerve impulse away from the neu-rone cell body.
What is meant by the "absolute refractory period" of a nerve cell membrane? The time during which: A. a larger than normal stimulus is required to cause an action potential. B. a smaller than normal stimulus will produce an action potential. C. no stimulus will produce an action potential. D. two stimuli in quick succession are required to add to an above threshold stimulus.
Answer is C: During the ~0.5 ms period of the action potential in which sodium ions are rushing into a nerve cell, the nerve cannot respond to any stimulus not matter how strong the stimulus. Because of the impossibility of response, this period is called "absolutely" refractive. (refractory = resisting ordinary methods).
Where is the autonomic control centre for most of body homeostasis located? A. In the limbic system B. In the brainstem C. In the hypothalamus D. In the cerebellum
Answer is C: Hypothalamus is the autonomic centre which is the main visceral control centre of body homeostasis.
What is true about the spino-thalamic tract? A. it is a descending pathway that carries sensory information B. it is a descending pathway that carries motor instructions C. it is an ascending pathway that carries sensory information D. it is an ascending pathway that carries motor instructions
Answer is C: It is ascending - going from spine to thalamus - and ascending tracts carry sensory information to the brain.
What event during the action potential causes the resting membrane potential to change from about −70 mV to about +30 mV? A . K + ions moving into the cell B. K + ions moving out of the cell C. Na + ions moving into the cell D. Na + ions moving out of the cell
Answer is C: It takes positive ions moving INTO the cell to change the resting potential from −70 to +30 mV. The ions are sodium.
Which of the following substances is prevented from entering the brain by the blood-brain barrier? A. glucose B. nicotine C. pharmaceuticals D. alcohol
Answer is C: Many pharmaceuticals are unable to cross the BBB.
Which neurons are unipolar? A. neurons in the central nervous system B. neurons in the retina C. sensory neurons D. motor neurons
Answer is C: Most sensory neurones are unipolar, that is the axon and dendrites are not separated by the cell body but are the one strand (are fused), with the cell body attached to it by a single process.
What name is given to the cells in the nervous system that produce nerve impulses? A. neurotransmitters B. nerves C. neurons D. neuroglia
Answer is C: Neurons produce nerve impulses, Nerves are bundles of neurones. Neuroglia are cells that support and protect neurones.
The hypothalamus does ALL of the following EXCEPT one. Which one? A. It is the autonomic control centre. B. It directs lower CNS centres to perform actions. C. It produces the rigidly programmed, automatic behaviours necessary for survival D. It performs many homeostatic roles.
Answer is C: Rigidly programmed automatic behaviours are controlled by the brainstem (midbrain, pons, medulla oblongata) not the hypothalamus.
What is the type of neuroglia that forms the myelin sheath on neurons outside of the CNS? A. Oligodendrocytes B. Satellite cells C. Schwann cells D. Microglia
Answer is C: Schwann cells surround the axon to form the myelin sheath in peripheral neurones. Oligodendrocytes perform a similar function for neurones in the CNS.
What can correctly be said about somatic motor neurons? A. they are unipolar neurons B. their cell bodies are in the dorsal root ganglia C. their cell bodies are located in the central nervous system D. they are bipolar neurons
Answer is C: Somatic motor neurons are multipolar. Their cell bodies are located in the CNS - within the spinal cord.
Where is that part of the brain that allows us to consciously control voluntary muscle movements located? A. post-central gyrus of parietal lobe B. pre-motor cortex of frontal lobe C. pre-central gyrus of the frontal lobe D. arbour vitae of the cerebellum
Answer is C: The "pre-motor cortex" in fact lies just anterior to the pre- central gyrus, which is the primary motor area. Your premotor cortex allows you make choices about which movement is appropriate.
What is the blood-brain barrier? A. It is the inner two meninges that surround the brain. B. It is formed by the capillaries of choroid plexus and ependymal cells. C. It is the endothelial cells of capillaries that supply the brain, and their astrocytes. D. It is the cerebrospinal fl uid that bathes the brain.
Answer is C: The BBB is the endothelial cells of the capillaries (which are joined by tight junctions), their basement membrane and the enveloping astro-cytic feet of the astrocytes (one of the cell types called neuroglia).
What part of the brain is known as the cerebrum? A. it is that part of the diencephalon that surrounds the third ventricle. B. it makes up the majority of the brain stem C. the superficial part consisting of sulci and gyri D. the dorsal inferior part adjacent to the occipital bone
Answer is C: The cerebrum is the cortex (the outer part) of the brain made up of folds called gyri and sulci.
In which of the following places would you NOT find cerebrospinal fluid? A. the sub-arachnoid space B. the third ventricle of the brain C. the epidural space D. the central canal of the spinal cord
Answer is C: The epidural space surrounds the dura mater of the spinal cord and so is outside of the meninges and of the CNS. "Epi-" means on top of the dura.
What is the gap between the plasma membranes of a neuron that conducts an incoming signal and the cell that is going to receive the signal called? A. neuromuscular junction B. intercellular cleft C. synaptic cleft D. intercalated disc
Answer is C: The gap between cells at a synapse is called a synaptic cleft. A neuromuscular junction is one type of synapse.
A difference in the amount and type of ions between the two sides of a plasma membrane or a charge difference that occurs when ions move along a mem-brane is called an "electrical potential". What does the term "action potential" refer to? A. The distribution of ions that results in the inside of the cell being at about −70 mV compared to outside the cell. B. A movement of sodium ions into the cell following a stimulus and the ions spreading out along the inside of the cell membrane. C. The rapid movement of sodium ions into the cell followed by potassium ions moving out of the cell, with the movement being repeated along the length of the neuron. D. Sodium ions being pumped out of the cell, while potassium ions are moved into the cell.
Answer is C: The infl ux of sodium ions followed by the effl ux of potassium ions describes the action potential. Choice A describes the "resting potential".
What is the purpose of the myelin sheath around an axon? A. To control the chemical environment around the nerve cell. B. To phagocytose microbes C. To prevent movement of ions through the nerve cell membrane D. To form the blood-brain barrier.
Answer is C: The myelin sheath insulates the axon. That is, it prevents ions from crossing the plasma membrane except at the nodes of Ranvier, where the sheath is absent.
What and where is the pre-central gyrus? A. It is the site of sensory function and is in the frontal lobe. B. It is the site of sensory function and is in the parietal lobe. C. It is the site of motor function and is in the frontal lobe. D. It is the site of motor function and is in the parietal lobe.
Answer is C: The pre-central gyrus of the frontal lobe is the primary motor area.
Which part of the brain allows us to control skilled voluntary muscle movements? A. basal nuclei B. cerebellum C. pre-central gyrus D. thalamus
Answer is C: The pre-central gyrus of the frontal lobe is the primary motor area. It controls voluntary movements of skeletal muscle.
What is the space between a neuron and the following neuron, muscle or gland that it stimulates called? A. Synaptic vesicle B. Ion channel C. Synaptic cleft D. Receptor
Answer is C: The synaptic cleft is the space over which an incoming nerve impulse is transmitted by a molecule called a neurotransmitter.
Which of the following is a characteristic of an action potential? A. The signal is graded B. It results due to an influx of potassium ions C. it is an all or none response D. It results from an initial outflow of sodium ions
Answer is C: When a graded potential exceeds the threshold for producing an action potential, the AP happens regardless of the strength of the graded potential. This is an all or none event. (Choice D is wrong as sodium ions should be moving IN).
Which best describes a nerve? A. dendrites, cell bodies, axons, Schwann cells B. dendrites, cell bodies, axon hillock, axon terminals, vesicles C. dendrites, cell bodies, axon hillock, axon terminals, Schwann cells, neurotransmitters D. axons, blood vessels, connective tissue, Schwann cells
Answer is D: A nerve is a bundle of axons of individual neurons. Hence does not contain nerve cell bodies. A nerve does include the Schwann cells around axons, BV and CT.
When is an action potential initiated? When A. the resting membrane potential changes from −70 mV to +30 mV. B. a nerve impulse has caused some muscle action to be produced. C. the potassium 'gates' in the cell membrane open and potassium ions fl ood into the cell. D. a stimulus, which is above the threshold level, is applied to a receptor.
Answer is D: A stimulus which exceeds the threshold level is required to gener-ate an action potential.
When an action potential arrives at a synapse, what happens first? A. a neurotransmitter is released into the synaptic cleft B. extracellular Na + crosses the post-synaptic membrane C. Choline in the synaptic cleft enters the nerve cell and is converted to acetyl choline D. extracellular Ca ++ enters the nerve cell
Answer is D: As the axon terminal depolarises when the action potential arrives, calcium channels open and extracellular calcium enters the axon terminal. This stimulates the release of a neurotransmitter (e.g. ACh) into the synaptic cleft.
Where is the cerebral spinal fluid found? A. Between the pia mater and the brain B. Between the dura mater and the arachnoid mater C. Between the dura mater and the pia mater D. Between the arachnoid mater and the brain
Answer is D: CSF is located in the sub-arachnoid space and within the brain.
What part of the brain subconsciously provides precise timing for the movements of learned skeletal muscle contraction? A. cerebrum B. diencephalon C. brainstem D. cerebellum
Answer is D: Cerebellum subconsciously provides precise timing and appro-priate patterns of learned skilled skeletal muscle contraction for smooth coor-dinated movements, posture & agility.
Which of the following describes an "action potential"? A. The high concentration of Na + and Cl − outside the cell, and of K + inside the cell. B. The voltage change that moves along the cell membrane until it reaches the axon hillock. C. The movement of a neurotransmitter from the pre-synaptic membrane to the post-synaptic membrane. D. The movement of Na + across the cell membrane into the cell, followed by the movement of K + out of the cell.
Answer is D: Choice B describes a graded potential. Choice C describes synap-tic transmission. Choice A describes the distribution of those ions that contrib-ute to the resting potential.
Which of the following substances CANNOT pass through the "blood-brain barrier"? A. steroid hormones B. O 2 molecules C. alcohol D. potassium ions
Answer is D: Fat soluble molecules can pass the BBB, but most charged parti-cles cannot.
Some cells in the body can maintain an electric potential across their cell membrane. How do they do this? A. By using the sodium-potassium pump to continually eject positive sodium and potassium ions from the cell. B. By allowing negative chloride ions to enter the cell along their concentra-tion gradient. C. By trapping large cations inside the cell membrane. D. By keeping unequal concentrations of various ions on each side of the cell membrane.
Answer is D: It is the distribution of ions of different charge on either side of the membrane that determines the membrane potential.
Which of the following statements is true of neuroglia? A. they are the cells that link motor neurons to sensory neurons B. it is the non-cellular material that lies between neurons C. they have only one dendrite and one axon D. they produce the myelin sheath
Answer is D: Neuroglia refers to several types of cells of the nervous system that are not neurones. Some of them form the myelin sheath.
Most sensory neurones may be described as which of the following? A. multipolar B. bipolar C. having cell bodies within the CNS D. unipolar
Answer is D: Sensory neurons are unipolar. And their cell bodies are outside the CNS in the dorsal root ganglia.
Which sequence of ion movements describes the action potential? A . N a + move out of cell then K + move in B. K + move in to cell then Na + move out C. K + move out of cell then Na + move in D. Na + move into cell then K + move out
Answer is D: Sodium ions are in high concentration outside the cell (and in low concentration inside the cell). The correct sequence is Na in followed by K out.
The action potential occurs when one of the following events occurs. Which one? A . N a + rushes into the cell followed by Cl − B. Na + rushes out of the cell followed by PO 43− rushing in C. K + rushes into the cell followed by Na + rushing out D. Na + rushes into the cell followed by K + rushing out
Answer is D: Sodium rushing in following by potassium rushing out produces the action potential.
What is the likely result of an injury that severs the spinal cord between C5 and C6? A. respiratory failure and death. B. paraplegia C. hemiplegia D. quadriplegia
Answer is D: Spinal nerves below the break cannot pass on impulses from the brain. So quadriplegia results because the spinal nerves that innervate the limbs leave the spinal cord below the level of the spinal cord break (except for some brachial nerves that leave at C5). Fortunately, the phrenic nerve, which inner-vates the diaphragm, leaves the spinal cord at C3, C4 and C5 so will still carry impulses from the brain. So breathing will continue.
What part of the neurone carries the "action potential"? A. the cell body B. the dendrites C. the synaptic knobs D. the axon
Answer is D: The action potential travels along the axon, away from the cell body.
What part of the brain contains the midbrain, the pons and the medulla oblongata? A. the diencephalon B. the cerebrum C. the cerebellum D. the brainstem
Answer is D: The brainstem consists of the midbrain, the pons and the medulla oblongata
What are the three meninges and two named "spaces" that surround the brain, in order from superficial to deep (outermost to innermost)? A. pia, arachnoid, sub-arachnoid, dura, septa B. sub-arachnoid, epidural, dura, pia, arachnoid C. arachnoid, sun-arachnoid, pia, epidural, dura D. epidural, dura, arachnoid, sub-arachnoid, pia
Answer is D: The dura mater, arachnoid mater and pia mater are the three meninges in order.
What does the term "synapse" refer to? A. the plasma membrane of the axon terminal of a nerve cell. B. that part of the plasma membrane of the cell being stimulated, that is oppo-site the axon terminal. C. the gap between the stimulating nerve cell and the receiving cell. D. the place where signal transmission between a nerve cell and the cell it is stimulating occurs.
Answer is D: The impulse carried by a nerve cell is transferred by neurotrans-mitter to the stimulated cell by this structure at the point of contact. Choice C describes the synaptic cleft.
Which statement is true of a multi-polar neuron? A. has many axons attached to the cell body B. is the major type of neuron in the peripheral nervous system C. all sensory neurons are multi-polar D. has many dendrites attached to the cell body
Answer is D: The many dendrites give the "multi-" part of the name of this type of neuron. Sensory neurones are unipolar.
What functions are controlled from the pre-central gyrus of the frontal lobe? A. automatic visceral functions B. conscious perception of many sensory inputs C. subconscious timing and co-ordination of skeletal muscle. D. voluntary control of skeletal muscle
Answer is D: The pre-central gyrus is the primary motor area of the brain.
Where in the brain is the "primary motor area"? A. Midbrain B. Thalamus C. Basal nuclei D. Pre-central gyrus
Answer is D: The pre-central gyrus of the frontal lobe is the primary motor area of the brain and is separated from the primary sensory area (the post-central gyrus), by the central sulcus
Inactive muscle and nerve cells maintain a resting membrane potential. This potential results in: A. the outside of the cell being negative B. the inside of the cell being positive C. the inside and outside of the cell having the same charge D. the inside of the cell being negative
Answer is D: The resting potential has the inside of the cell at about −70 mV compared to the outside.
The sequence of events that constitute an action potential is correctly described by which of the following? Resting potential of..... A. +35 mV, stimulus above the threshold, Na + move into cell, depolarisation to −70 mV, K + move out of cell, repolarisation to +35 mV. B. −70 mV, stimulus above the threshold, K + move into cell, depolarisation to −35 mV, Na + move out of cell, repolarisation to −70 mV. C. +35 mV, stimulus above the threshold, K + move into cell, depolarisation to −70 mV, Na + move out of cell, repolarisation to +35 mV. D . −70 mV, stimulus above the threshold, Na + move into cell, depolarisation to +35 mV, K + move out of cell, repolarisation to −70 mV.
Answer is D: The resting potential is negative, and the fi rst ion movement is sodium ions into of the cell.
Which of the following are NOT part of the cerebral cortex? A. motor areas, sensory areas and association areas B. pre-central gyrus and post-central gyrus C. white matter and basal nuclei D. the lateral ventricles and the thalamus
Answer is D: The thalamus is part of the diencephalon, not the cerebral cortex (cerebrum)
What part of the brain receives sensory input before passing it on to another part of the brain for interpretation or action? A. pons B. hypothalamus C. post-central gyrus D. thalamus
Answer is D: The thalamus relays visual & auditory information
