PSY 232 Chapter 8
The pathway indicated by the number 3 in the figure originates in the ____________________ and is known as the ____________________ tract.
Blank #1 - superior colliculus, midbrain, or tectum; Blank #2 - Tectospinal(see Figure 8.16)
When an action potential arrives at the muscle fiber, calcium is released internally and binds with troponin. a. True b. False
True
. One of the actions of the basal ganglia is the a. inhibition of the thalamus. b. excitation of the hypothalamus. c. inhibition of the cerebellum. d. excitation of the cerebrum.
a
A disorder produced by the degeneration of ACh receptors is known as a. myasthenia gravis. b. muscular dystrophy. c. Parkinson's disease. d. Huntington's disease.
a
A muscle relaxes after contracting when a. calcium is taken up by internal organelles. b. internal acetylcholine is broken apart by acetylcholinesterase. c. troponin is taken up by internal organelles. d. myosin and actin begin to interact.
a
A person with damage to the right hemisphere motor cortex will experience weakness or paralysis a. on the left side of the body. b. on the right side of the body. c. on both the right and left sides of the body. d. in the torso and arms but not the legs.
a
Age-related loss in muscle mass appears to begin around the age of _________ years. a. 25 b. 30 c. 75 d. 90
a
Cases of polio may be found in a. human beings, whales, and chimpanzees. b. human beings only. c. human beings and any other primate. d. human beings and any animal species.
a
Droopy eyelids, slurred speech, and difficulty swallowing and breathing are characteristic of a. myasthenia gravis. b. muscular dystrophy. c. Parkinson's disease. d. Huntington's disease.
a
Genetic abnormalities are probably most directly responsible for a. muscular dystrophy and Huntington's disease. b. polio and muscular dystrophy. c. Huntington's disease and polio. d. tetanus and polio.
a
Genetics may predispose people to developing_________ Parkinson's disease. a. early onset, but not late-onset b. late-onset, but not early onset c. both early onset and late-onset d. neither early onset nor late-onset
a
In a resting muscle fiber, _________ is covered by a protein called _________. a. actin; troponin b. actin; calcium c. myosin; troponin d. myosin; calcium
a
Input from Ib sensory fibers a. inhibits the activity of alpha motor neurons. b. activates alpha motor neurons. c. contracts muscle spindles. d. contracts muscles.
a
Intrafusal muscle fibers a. are found in muscle spindles. b. are responsible for muscle contractions. c. provide feedback regarding muscle contractions. d. are located at the junction between a muscle and tendon.
a
Justin is a medical student. Compared with carrying out a simple movement like tapping his foot, performing precise and complicated movements during surgery will require Justin to make greater use of his a. premotor cortex. b. tectospinal tract c. cerebellum. d. subthalamic nucleus.
a
Motor neurons with small cell bodies usually innervate _________ muscle fibers. a. Type I b. Type IIa c. Type IIb d. combinations of Type IIa and Type IIb
a
Muscles that straighten joints are known as a. extensors. b. flexors. c. antagonists d. relaxers.
a
Nutrients are moved through the digestive tract by _________ muscle. a. smooth b. cardiac c. striated d. both smooth and striated
a
People with spinal cord injuries show a loss of _________ muscle fibers. a. slow-twitch b. slow-twitch and fast-twitch c. fast-twitch d. autonomic
a
Primary motor cortex is located in the _________ gyrus of the _________ lobe. a. precentral; frontal b. precentral; parietal c. postcentral; frontal d. postcentral; parietal
a
Recruitment proceeds in a way that ensures that the a. least amount of energy and force possible will be used to do a job. b. greatest amount of energy and force possible will be used to do a job. c. fastest fibers will be recruited first to produce optimum reaction time. d. fibers with the greatest oxygen requirements will be used only when absolutely necessary for survival.
a
Sherry had some spinal cord damage, and she now has difficulty mostly with fine movement. More specifically, she had damage to the _________ pathway in her spinal cord. a. lateral b. ventromedial c. rostral-tegmental d. dorsomedial
a
Single segments of a myofibril are called a. sarcomeres. b. twitches. c. Z lines. d. troponins.
a
Slow-twitch fibers and fast-twitch fibers are both a type of a. myosin filament. b. actin filament. c. myofibril. d. sarcomere.
a
Spinal motor neurons responsible for contracting muscles are known as _________ motor neurons. a. alpha b. beta c. gamma d. theta
a
The Babinski sign occurs when a. stroking the sole of the foot causes the toes to spread and the big toe to point upward. b. stroking the sole of the foot causes the toes to curl and then separate. c. tapping the knee with a small hammer causes the foot to kick. d. both extensors and flexors at a joint contract simultaneously in violation of reciprocal inhibition.
a
The basal ganglia influence voluntary movement by a. directly inhibiting the thalamus, which in turn influences the premotor cortex and SMA. b. directly inhibiting the premotor cortex and SMA, which in turn influences the thalamus. c. making direct connections with primary motor cortex. d. directly activating the thalamus, which in turn influences pre-SMA and SMA.
a
The lateral pathway originates in the _________ and controls _________ movements. a. cerebral cortex; voluntary b. cerebral cortex; automatic c. brainstem; voluntary d. brainstem; automatic
a
The most important target(s) for output from primary motor cortex is (are) a. either the red nucleus or alpha motor neurons. b. the superior and inferior colliculi of the midbrain. c. the vestibular nuclei of the brainstem. d. the reticular formation of the brainstem.
a
The pontine reticulospinal tract originates in the a. reticular formation of the pons. b. reticular formation of the medulla. c. vestibular nuclei of the medulla. d. midbrain.
a
Vaccinations effectively prevent which of the following disorders? a. polio b. muscular dystrophy c. myasthenia gravis d. Huntington's disease
a
What causes muscles to twitch? a. depolarization of the muscle fiber produced by an influx of sodium ions b. depolarization of the muscle fiber produced by an influx of potassium ions c. hyperpolarization of the muscle fiber produced by an influx of calcium ions d. hyperpolarization of the muscle fiber produced by an outflow of potassium ions
a
Which of the following disorders is caused by a virus that targets and destroys spinal alpha motor neurons? a. polio b. muscular dystrophy c. myasthenia gravis d. Huntington's disease
a
Which of the following statements about muscle movement is true? a. The only thing that muscles can do is contract. b. A single muscle can bend a joint by contracting and straighten it by relaxing. c. Smooth muscles cause movement by contracting, while striated muscles cause movement by contracting and relaxing. d. Striated muscles cause movement by contracting, but smooth muscles cause movement by contracting and relaxing.
a
saac observed a sample of motor units in which single neurons innervated fibers of the same type. This led Isaac to conclude that a. neural input probably determines the identity of muscle fibers as slow or fast-twitch. b. the organism that supplied the samples had probably suffered a spinal cord injury. c. the organism that supplied the samples was very old. d. his sample was not representative, and he needed to obtain more samples before reaching a conclusion.
a
the structure indicated by the number 3 in this image is a. myofibril. b. z-line. c. sarcomere. d. motor end plate.
a
Dystrophin, the protein that is affected by muscular dystrophy, normally acts to a. protect muscle fiber membranes during movement. b. clear the interior of muscle fibers of excess calcium. c. allow myosin and actin to interact during muscle contraction. d. protect muscle spindles from too much stretching during movement.
a
Neurons controlling voluntary movement of the head are located in the a. ventral portions of the precentral gyrus. b. dorsal portions of the postcentral gyrus. c. supplementary motor area. d. cerebellum.
a
. An athlete with likely potential in Olympic weightlifting would probably have _________ in the quadriceps muscle. a. about the same number of fast- and slow-twitch fibers b. more fast- than slow-twitch fibers c. more slow- than fast-twitch fibers d. only fast-twitch muscles
b
A disorder characterized by extreme difficulties in producing movement is known as a. amyotrophic lateral sclerosis. b. Parkinson's disease. c. Huntington's disease. d. myasthenia gravis.
b
A single alpha motor neuron and the muscle fibers it innervate are known as a(n) a. motor junction. b. motor unit. c. intrafusal unit. d. antagonistic unit.
b
Abnormalities in muscle fiber proteins characterize a. myasthenia gravis. b. muscular dystrophy. c. Parkinson's disease. d. Huntington's disease.
b
According to PET scans, which of the following areas are the first to show activity when a voluntary movement is initiated? a. the occipital and temporal lobes b. the parietal and frontal lobes c. the supplementary motor area and the premotor area d. the premotor area and the parietal lobes
b
Action potentials in muscle fibers a. do not occur. b. spread out in two directions on either side of a receptor site. c. travel in only one direction, from one end of a muscle fiber to the other. d. lead to multiple twitches in that fiber.
b
Activity in the basal ganglia is higher than normal in cases of a. Alzheimer's disease. b. Huntington's disease. c. major depressive disorder. d. muscular dystrophy.
b
Alcohol exerts a negative effect on motor coordination particularly through its action on the a. basal ganglia. b. cerebellum. c. reticular formation. d. red nucleus.
b
As you bend your arm up to take a drink, the ________ muscles are active, and when you extend your arm to put the glass down, the ________ muscles are active. a. striated; smooth b. flexor; extensor c. extensor; flexor d. Type II; Type I
b
Degeneration of dopaminergic neurons of the substantia nigra is implicated in a. amyotrophic lateral sclerosis. b. Parkinson's disease. c. Huntington's disease. d. myasthenia gravis.
b
Degeneration of motor neurons in the brainstem and spinal cord is characteristic of a. polio. b. amyotrophic lateral sclerosis. c. muscular dystrophy. d. myasthenia gravis.
b
Extrafusal muscle fibers a. are found in muscle spindles. b. are responsible for muscle contractions. c. provide feedback regarding muscle contractions. d. are located at the junction between a muscle and tendon
b
Feedback regarding joint position and movement is provided by a. muscle spindles. b. mechanoreceptors. c. Golgi tendon organs. d. free nerve endings.
b
Golgi tendon organs provide feedback about a. muscle stretch. b. force. c. position. d. movement.
b
Intrafusal fibers receive input from a. alpha motor neurons. b. gamma motor neurons. c. Ia sensory fibers. d. C fibers.
b
Motor units that include Type IIb fibers a. usually include Type IIa fibers as well. b. produce about 100 times the force as units that include Type I fibers. c. produce about one-third of the force produced by units that include Type IIa fibers. d. are rarely found in humans.
b
Myasthenia gravis a. may be treated by administering dopamine agonists. b. may be treated with medications that suppress the immune system. c. may be treated with the implant of fetal stem cells. d. has no current effective treatments.
b
Observations of the muscle fibers of people who have experienced spinal cord damage suggest that neural input is especially important to the maintenance of a. fast-twitch fibers. b. slow-twitch fibers. c. both fast and slow-twitch fibers. d. neither fast nor slow-twitch fibers.
b
Reciprocal inhibition is a simple type of _________ reflex. a. monosynaptic. b. polysynaptic c. flexion d. withdrawal
b
Rigor mortis, or the muscle stiffness present after death, results primarily from a. a drop in acetylcholine levels. b. a lack of energy needed to separate actin and myosin molecules. c. an increase in intracellular calcium concentrations. d. the breakdown of troponin molecules.
b
Single-cell recordings during movement indicate that a. movements are encoded by single neurons. b. movements are encoded by populations of neurons. c. it is not possible to identify correlations between neural activity and movements. d. neural activity during movement appears surprisingly random.
b
Taiwanese cobra venom a. causes paralysis by preventing neurotransmitter release. b. causes paralysis by blocking postsynaptic receptors. c. interferes with neurotransmitter synthesis. d. produces convulsions by stimulating neurotransmitter release.
b
The Babinski sign is a. normal in adults but not in children. b. normal in children but not adults. c. normal in both adults and children. d. abnormal in both adults and children.
b
The arrival of an action potential in a muscle fiber causes a. calcium to enter the muscle fiber. b. calcium to be released by internal organelles. c. acetylcholine to enter the muscle fiber. d. acetylcholine to be released by internal organelles.
b
The long strands of protein running the length of a muscle fiber are called a. sarcomeres. b. myofibrils. c. Z lines. d. troponins.
b
The medullary reticulospinal tract originates in the a. reticular formation of the pons. b. reticular formation of the medulla. c. vestibular nuclei of the medulla. d. midbrain.
b
The premotor cortex and SMA converge on very large cells located in _________ of primary motor cortex. a. pyramidal cells in Layer III. b. pyramidal cells in Layer V c. Purkinje cells in Layer III d. Purkinje cells in Layer V
b
The reason the homunculus for the motor cortex is shaped the way it is (huge tongue, large hands) is that a. it is a drawing of all the motor functions of the body, and it is not drawn to scale. b. the amount of cortex devoted to each part of the body is represented by the relative size of the body part. c. it is a reproduction of a drawing done the late eighteenth century. d. there is an inverse relationship between the actual size of each body part to its representation in the homunculus drawing.
b
The structure indicated by the number 2 in this image is known as a(n) a. extrafusal fiber. b. Ia sensory fiber. c. gamma motor fiber. d. intrafusal fiber.
b
Traditional therapy for Parkinson's disease often includes a. medication to inhibit dopamine production. b. medication to stimulate dopamine production. c. gene replacement therapy. d. caspase inhibitors.
b
Ventromedial pathways provide a. automatic control of the hands, feet, and parts of limbs farther from the body. b. automatic control of the neck, torso, and parts of limbs close to the body. c. voluntary control of the hands, feet, and the medial sections of limbs. d. voluntary control of the neck and torso.
b
What happens to the rate of firing in motor neurons as we age? a. No changes occur. b. Firing rates decrease, leading to slower and weaker muscle responses. c. Firing rates increase, leading to uncomfortable cramping. d. Firing rates decrease, but muscle fibers are able to compensate for these changes.
b
When an Olympic weightlifter uses explosive strength to lift a personal best, the _________ fibers in her legs are probably the most active, but the marathon runner relies on her _________ fibers. a. slow twitch; fast twitch b. fast twitch; slow twitch c. Type I; Type III d. Type III; Type II
b
Where should we look to find Ia sensory fibers? a. at the neuromuscular junction where they are forming synapses with muscle fibers b. wrapped around the middle sections of muscle spindle fibers c. in the junctions between muscles and tendons d. in joints and in the skin
b
Which of the following is a sex-linked disorder? a. myasthenia gravis b. muscular dystrophy c. Parkinson's disease d. Huntington's disease
b
Which of the following structures is part of the basal ganglia? a. the red nucleus b. the putamen c. the cerebellum d. the reticular formation
b
Your friend was in an accident, and although his intelligence and personality are unchanged, he is no longer able to play his guitar, nor is he the coordinated athlete he once was. His symptoms may be the result of damage to which of the following areas? a. the frontal lobes b. the cerebellum c. the occipital lobes d. the hippocampus
b
temporal summation may occur at the neuromuscular junction because a. action potentials last longer than muscle contractions. b. muscle contractions last longer than action potentials. c. many motor neurons form synapses at a single neuromuscular junction. d. acetylcholine is broken down slowly in the synaptic gap.
b
. One major difference between striated and smooth muscles is that a. smooth muscles move the voluntary system and striated muscles move automatic systems. b. striated muscles are responsible for fast twitch and smooth muscles are responsible for slow twitch. c. striated muscles move mostly voluntary systems while smooth muscles move involuntary, automatic systems. d. smooth muscles are made up of myofibrils and striated muscle is made up of only sarcomeres.
c
A Z line is a. a segment of myofibril. b. a type of muscle fiber. c. the boundary of a sarcomere. d. the path of a muscular action potential.
c
A single motor unit usually contains a motor neuron and a. one muscle fiber. b. both fast and slow-twitch fibers. c. either fast-twitch or slow-twitch fibers, but not a mixture of the two types. d. a muscle spindle.
c
Activity in the basal ganglia is lower than normal in cases of a. Alzheimer's disease. b. Huntington's disease. c. Parkinson's disease. d. muscular dystrophy.
c
Age-related changes in muscle function a. are related to genetics and cannot be changed. b. can be completely stopped through exercise. c. cannot be stopped, but people can compensate somewhat for these changes by exercising. d. cannot be stopped, but people can compensate somewhat for these changes by eating carefully.
c
An antagonistic pair of muscles is made up of a. two extensor muscles at the same joint. b. two flexor muscles at the same joint. c. an extensor muscle and a flexor muscle at the same joint. d. two complex muscles that allow joints like hips and elbows to move in many directions
c
Bending a joint requires a. relaxation of extensors and flexors. b. contraction of extensors and flexors. c. relaxation of extensors and contraction of flexors. d. contraction of extensors and relaxation of flexors.
c
Compared to the muscles of young adults, the muscles of elderly people a. contain fibers that are more angular than round. b. show a more even distribution of slow and fast twitch fibers. c. are more likely to be hybrids of fast and slow twitch fibers. d. are more likely to be made up of slow twitch fibers.
c
Compared with other sensory neurons, such as those that serve mechanoreceptors, Ia sensory fibers are a. far less commonly found in the human nervous system. b. less likely to be myelinated in the human nervous system. c. very large and very fast. d. very small and slow.
c
Drinking coffee is correlated with lower rates of a. Huntington's disease. b. amyotrophic lateral sclerosis. c. Parkinson's disease. d. polio.
c
Elizabeth's grandmother recently underwent a hip replacement operation. Because she took this course, Elizabeth is able to tell her grandmother that she a. will need to be very careful, because the removal of her joint receptors means that she will not know the position of her hip without looking. b. will have to relearn how to walk, as the operation removes joint receptors responsible for managing muscle stretch. c. will still know the position of her hip without looking, even though her operation will remove all of her joint receptors. d. should prepare to deal with phantom pain from the joint receptors that have been removed.
c
Endurance activities, such as distance running, rely primarily on _________ muscles using _________ metabolism. a. fast-twitch; aerobic b. fast-twitch; anaerobic c. slow-twitch; aerobic d. slow-twitch; anaerobic
c
Exposure to environmental toxins may lead to a. Huntington's disease. b. amyotrophic lateral sclerosis. c. Parkinson's disease. d. polio.
c
Fast-twitch fibers contract up to _________ times more rapidly than slow-twitch fibers. a. 3 b. 8 c. 10 d. 12
c
Ia sensory fibers are activated in response to a. contraction of muscle fibers. b. stretching of Golgi tendon organs. c. stretching of muscle fibers. d. input from Ib fibers.
c
In which of the following locations would we expect to find the greatest density of muscle spindles? a. the legs b. the torso c. the hands d. the arms
c
Muscle spindles are responsible for a. providing feedback regarding muscle contraction. b. providing feedback regarding position of joints. c. providing feedback regarding muscle length. d. contracting muscles.
c
Quadriplegia usually results from a. polio. b. muscular dystrophy. c. spinal cord damage at the cervical level. d. spinal cord damage at the lumbar level.
c
Rey was being evaluated for a possible spinal cord injury during a college football game. The team physician stroked the sole of Rey's foot, and his toes curled. This observation suggests that a. Rey has a serious spinal cord injury that might affect his future mobility. b. Rey has a mild spinal cord injury, and with proper treatment, he should recover completely. c. Rey does not appear to have damaged his spinal cord, although this should be confirmed by further testing. d. Rey's spinal cord is probably all right, but it appears that he has sustained damage to his foot or ankle.
c
Slow-twitch muscle fibers are to _______ as fast-twitch muscle fibers are to _______. a. Ia: Ib b. IIa; Ia c. I; IIa & IIb d. IIb; IIa
c
The lower gravity experienced by astronauts a. does not affect muscle mass. b. increases muscle mass. c. decreases muscle mass. d. converts fast-twitch muscles to slow-twitch muscles.
c
The lungs are moved by _________ muscle a. smooth b. cardiac c. striated d. both smooth and striated
c
The muscles of the arms and shoulders contain a. approximately equal amounts of fast and slow-twitch fibers, making them well-suited for both endurance and explosive movements. b. higher proportions of slow-twitch fibers, making them better suited for endurance than for explosive movements. c. higher proportions of fast-twitch fibers, making them better suited for explosive movements than for endurance movements. d. higher proportions of fast-twitch fibers, making them better suited for endurance than for explosive movements.
c
The patellar tendon or "knee jerk" reflex is an example of a _________ reflex. a. withdrawal b. flexion c. monosynaptic d. polysynaptic
c
The pathways illustrated in the left side of this figure (numbers 1 and 2) are known as the a. medial lemniscus. b. spinothalamic pathways. c. lateral pathways. d. ventromedial pathways.
c
The proportion of fast and slow-twitch fibers found in an individual's quadriceps muscle is primarily determined by the a. individual's diet. b. number of hours the individual spends each week engaged in anaerobic activity, like weightlifting. c. the number of ACTN3 genes that person has d. number of hours the individual spends each week engaged in aerobic activity, like running or cycling.
c
The rubrospinal tract originates in the a. reticular formation of the brainstem. b. superior colliculi of the pons. c. red nucleus of the midbrain. d. vestibular nuclei of the thalamus.
c
The sequencing of complex movements is managed by the a. basal ganglia. b. red nucleus. c. cerebellum. d. reticular formation.
c
The vestibulospinal tract originates in the a. reticular formation of the pons. b. reticular formation of the medulla. c. vestibular nuclei of the medulla. d. midbrain.
c
Theory of mind (TOM), the understanding of another person's perspective, appears to be difficult for individuals with autism spectrum disorder. Consequently, researchers suspect that this condition may have a negative impact on a person's _________ neurons. a. vector b. reciprocal c. mirror d. pyramidal
c
What is the function of striated muscles? a. control blood pressure and move the eyes and lung b. move nutrients through the digestive tract and move bones c. control the heart and skeletal muscles d. control blood pressure and move the heart
c
Which of the following disorders appears to be more common in lean individuals who participated in college level athletics? a. polio b. muscular dystrophy c. amyotrophic lateral sclerosis d. myasthenia gravis
c
Which of the following is NOT one of the ventromedial motor pathways? a. the reticulospinal tract b. the tectospinal tract c. the rubrospinal tract d. the vestibulospinal tract
c
Which of the following sequences describes the typical order in which motor units are recruited? a. Type IIb, Type IIa, Type I b. Type II b, Type I, Type IIa c. Type I, Type IIa, Type IIb d. Type I, Type IIb, Type IIa
c
While typing on your keyboard, you are especially dependent on which of the following motor pathways? a. the tectospinal tract b. the vestibulospinal tract c. the lateral pathway d. the ventromedial pathway
c
You are going home one night when you drive through a sobriety checkpoint. The policeman asks you to get out of the car, holds one finger up in front of your face, and asks you to follow his finger with your eyes only. What is he doing? a. He is checking to see if your frontal lobe is functioning properly, which allows you to initiate movement. b. He is checking to see if your caudate nucleus, which coordinates your movements, has been affected by alcohol. c. He is checking to see if your cerebellum is functioning properly because the cerebellum is one of the first areas to be affected by alcohol. d. He is checking to see if you will follow directions because if you are drunk you might not.
c
________ is a protein that makes up the thin filaments of myofibril. a. Pectin b. Myosin c. Actin d. Sarcomere
c
In humans, which of the following body parts probably has the greatest corresponding area of primary motor cortex? a. the torso b. the legs c. the lips d. the toes
c
Many toxins responsible for motor disorders interact with the neurotransmitter a. serotonin. b. GABA. c. acetylcholine (ACh). d. glutamate.
c
Neurons that fire when an organism either carries out a movement or observes another organism carrying out the same movement are known as _________ neurons. a. vector b. reciprocal c. mirror d. pyramidal
c
A history of having applied insecticides and herbicides to one's garden is related to which of the following disorders? a. Huntington's disease b. myasthenia gravis c. muscular dystrophy d. Parkinson's disease
d
Alpha motor neurons are a. small and unmyelinated. b. small and myelinated. c. large and unmyelinated. d. large and myelinated.
d
Alpha motor neurons form connections with muscle fibers at the a. muscle spindle. b. antagonistic joint. c. motor unit. d. neuromuscular junction.
d
Alpha motor neurons receive input from a. neurons in muscle spindles only. b. neurons in muscle spindles and Golgi tendon organs. c. spinal interneurons and neurons of the brainstem and motor cortex. d. neurons in muscle spindles and Golgi tendon organs, neurons of the brainstem and motor cortex, and spinal interneurons.
d
Black widow spider venom a. causes paralysis by preventing GABA release. b. causes paralysis by blocking postsynaptic receptors. c. interferes with glutamate synthesis. d. produces convulsions by overstimulating acetylcholine release.
d
Brandon loves to spend many hours per week in the weight room, and he is quite muscular. Brandon's muscles have enlarged as a result of a. scar tissue. b. the breakdown of sarcomeres and Z lines. c. the production of more troponin. d. the production of more actin and myosin filaments.
d
Golgi tendon organs are innervated by a. Ia sensory fibers. b. alpha motor neurons. c. gamma motor neurons. d. Ib fibers.
d
In addition to its involvement with motor disorders, which of the following structures has been implicated in obsessive-compulsive disorder and attention deficit/hyperactivity disorder? a. the cerebellum b. the thalamus c. the red nucleus d. the basal ganglia
d
Motor neurons are a. evenly distributed throughout the gray matter of the spinal cord. b. evenly distributed throughout the white matter of the spinal cord. c. more numerous in spinal segments serving the middle torso. d. more numerous in spinal segments serving the arms and legs.
d
Muscle fibers contract when Z lines move _________ and the sarcomeres _________. a. farther apart; stretch b. farther apart; shorten c. closer together; stretch d. closer together; shorten
d
Muscle fibers respond to a. serotonin. b. glutamate. c. dopamine. d. acetylcholine.
d
Muscles dominated by slow-twitch fibers appear _________ due to the presence of _________. a. white; calcium b. white; myoglobin c. red; calcium d. red; myoglobin
d
Muscular dystrophy a. is usually treated with AChE inhibitors. b. may be treated with medications that suppress the immune system. c. may be treated with dopamine agonists. d. has no currently approved effective treatments.
d
Paraplegia usually results from a. polio. b. muscular dystrophy. c. spinal cord damage at the cervical level. d. spinal cord damage at the lumbar level.
d
Samantha is about to hand Megan a notebook that contains her biological psychology notes. Which of the following correctly describes how Megan's muscles will react to the heavy notebook? a. The weight of the notebook will cause Megan's arm muscles to contract. This information will be sensed by mechanoreceptors around her joints and sent to her spinal cord via Ib fibers. The Ib fibers will excite gamma motor neurons, which will cause her arm to contract further to adjust to the heavier weight of the book. b. The weight of the notebook will cause Megan's arm muscles to stretch. This information will be sensed by her spindles, and sent to her spinal cord by gamma motor neurons. The gamma motor neurons will inhibit the alpha motor neurons, causing her arm muscles to relax enough that she won't drop the book. c. The weight of the notebook will cause Megan's arm muscles to contract. This information will be sensed by her Golgi tendon organs, and sent to her spinal cord by Ib sensory fibers. The Ib sensory fibers will excite alpha motor neurons that will cause her arm muscles to stretch enough that she won't drop the book. d. The weight of the notebook will cause Megan's arm muscles to stretch. This information will be sensed by her spindles, and sent to her spinal cord by Ia sensory fibers. The Ia sensory fibers will excite alpha motor neurons that will cause her arm muscles to contract enough that she won't drop the book.
d
Stem cell transplantation may, in the future, be used to treat a. polio. b. myasthenia gravis. c. amyotrophic lateral sclerosis. d. Parkinson's disease.
d
The _________ tracts are part of the lateral pathway. a. tectospinal and rubrospinal b. vestibulospinal and tectospinal c. corticospinal and reticulospinal d. rubrospinal and corticospinal
d
The corticospinal tract crosses the midline at the level of the a. superior colliculi of the midbrain. b. junction between the midbrain and pons. c. junction between the pons and medulla. d. junction between the medulla and spinal cord.
d
The fact that symptoms of Huntington's disease include the inability to control voluntary movements makes sense because the major damage from Huntington's seems to be in the: a. motor cortex, which controls planned movements. b. cerebellum, which controls coordinated movements. c. spinal cord, which is the final pathway for all movements. d. basal ganglia, which participates in the initiation and control of fine motor movements.
d
The force of a movement is most directly controlled by a. the rate of motor neuron firing alone. b. recruitment of motor units alone. c. feedback from muscle spindles and recruitment. d. the rate of motor neuron firing and recruitment.
d
The premotor cortex and the supplementary motor area (SMA) receive substantial direct input from the a. basal ganglia. b. cerebellum. c. red nucleus. d. thalamus.
d
The preventing of one member of an antagonist pair of muscles whenever its partner is active is known as a. a monosynaptic reflex. b. a withdrawal reflex. c. a flexion reflex. d. reciprocal inhibition.
d
The rapid removal of your hand from a hot surface is the result of a. reciprocal inhibition. b. a monosynaptic reflex. c. an extensor reflex. d. a flexor reflex.
d
The separation of actin molecules from myosin molecules requires a. calcium. b. sodium. c. acetylcholine. d. energy.
d
The tectospinal tract originates in the a. reticular formation of the pons. b. reticular formation of the medulla. c. vestibular nuclei of the medulla. d. tectum of the midbrain.
d
Which of the following areas of the spinal cord show enlargement of the ventral horns due to large numbers of motor neurons? a. C1-C2 and T2-T12 b. C1-C2 and L1-S3 c. C3-T1 and T2-T12 d. C3-T1 and L1-S3
d
Without input from the gamma motor neurons, a. extrafusal muscle fibers would be unable to contract. b. intrafusal muscle fibers would not be able to relax. c. extrafusal fibers would go limp whenever intrafusal fibers contracted d. intrafusal fibers would go limp whenever extrafusal fibers contracted.
d
A person with fewer than 35 repeats of a specific gene, will probably remain healthy; those with 39 or more repeats of that same gene will develop ________. a. amyotrophic lateral sclerosis b. asthma c. Parkinson's disease d. Huntington's disease
d
Black widow spider venom affects movement by blocking receptors for acetylcholine in the postsynaptic membrane. a. True b. False
false
Complex plans for movement are correlated with decreased activity in the premotor cortex. a. True b. False
false
Golgi tendon organs send information to the spinal cord through Ia sensory fibers. a. True b. False
false
Muscular dystrophy results from exposure to some viruses. a. True b. False
false
The rubrospinal tract is one of the ventromedial motor pathways. a. True b. False
false
When we bend a joint, flexors relax while extensors contract. a. True b. False
false
The two types of fiber in this figure are the ____________________ fibers indicated by the number 1 and the ____________________ fibers indicated by the number 4.
intrafusal, extrafusal
In this image, the number 4 indicates ____________________ filaments, the number 5 indicates ____________________ filaments, and the number 7 indicates a ____________________.
myosin, actin, sarcomere
A motor unit is made up of one alpha neuron and all of the muscle fibers that it innervates. a. True b. False
true
Flexion reflexes, such as our withdrawal of our foot away from a sharp object, are examples of polysynaptic reflexes. a. True b. False
true
The basal ganglia inhibit the activity of the thalamus. a. True b. False
true
