block 5 lecture 12 testing the muscles

Question 1

what are the three main types of movement?

Answer 1

reflex, rhymthmic, voluntary

Question 2

what are the divisions of the motor system?

Answer 2

pyramidal and extrapyramidal

Question 3

where do the upper motor neurons arise?

Answer 3

in the primary motor cortex

Question 4

what do the upper motor neurons descend in?

Answer 4

the spinal cord

Question 5

where do most upper motor neurons decussate?

Answer 5

medulla

Question 6

what does the decussation of the upper motor neurons in the medulla give rise to?

Answer 6

lateral corticospinal tract

Question 7

what is the tract called of those upper motor neurons that dont decussate in the m edulla?

Answer 7

ipsilateral corticospinal tract

Question 8

where do the upper motor neurons synapse in the spinal cord?

Answer 8

spinal level of relevant spinal nerve with anterior horn cells

Question 9

what are the inputs for movement to be coordinated?

Answer 9

premotor cortex, cerebellum/brain stem and directly by spinal reflexes

Question 10

what is the extra-pyramidal system for?

Answer 10

balance, coordination, fine movement

Question 11

what are the pyramidal tracts through?

Answer 11

cortocospinal tracts

Question 12

what would you observe with upper motor neuron lesions?

Answer 12

muscle weakness, increased muscle tone, exaggerated reflex, clasp knife response, babinski sign

Question 13

what would you expect to see with lower motor neuron lesions?

Answer 13

muscle weakness, reduced muscle tone, absent reflexes, muscle atrophy, muscle fasiculation

Question 14

what do you get with extrapyramidal lesions?

Answer 14

dystonia, akisthisia, parkinsonism, dyskinesia

Question 15

what is dystonia?

Answer 15

spasms

Question 16

what is akisthisia?

Answer 16

motor restlessness`

Question 17

dyskinesia?

Answer 17

jerky movements

Question 18

what do you get with cerebellar lesions?

Answer 18

ipsilateral loss of coordination, past-pointing, disdiadochokinesia, ataxic gait, nystagmus,, dysarthria

Question 19

disdiadochokinesia

Answer 19

ability to change direction quickly

Question 20

nystagmus

Answer 20

rapid eye movements

Question 21

dysarthria

Answer 21

muscles of speech affected

Question 22

examples of upper motor neuron lesions?

Answer 22

stroke,MS,traumatic brain injury, cerebral palsy

Question 23

examples of lower motor neuron lesions?

Answer 23

bells palsy, gillian bare syndrome, motor neurone diseases

Question 24

what happens in brown sequard syndrome?

Answer 24

half the spinal cord is damaged

Question 25

what are the consequences of brown sequard syndrome?

Answer 25

loss of ipsilateral fine touch and proprioception | loss of controlateral pain and temperature

Question 26

what is anterior cord syndrom caused by?

Answer 26

damage to circulation

Question 27

what are the consequences of anterior cord syndrome?

Answer 27

loss of pain and temperature

Question 28

what happens to fine touch and proprioception in anterior cord syndrome?

Answer 28

preserved fine touch and proprioception

Question 29

what happens in central cord syndrome?

Answer 29

variable sensory loss, motor deficits more in upper limbs

Question 30

what are myofibril gathered into?

Answer 30

muscle fibers

Question 31

wheredo motor neurons synapse with muscle?

Answer 31

neuromuscular junction

Question 32

what happens when the neurotransmitters released?

Answer 32

the sarcolemma propagates an action potantial

Question 33

what does the action potential generated in the sarcolemma travel down?

Answer 33

T tubules

Question 34

what does the action potential traveling down the T tubules cause?

Answer 34

causes the sarcoplasmic reticulum to release calcium

Question 35

what does calcium cause?

Answer 35

acts on myofibrils allowing muscle to shorten

Question 36

what happens when calcium exposes the binding site between the actin and myosin?

Answer 36

the filaments slide over one another

Question 37

when is energy needed during muscle contraction?

Answer 37

to break bonds

Question 38

where does the sarcoplasmic reticulum release the calcium ions to during muscle contraction?

Answer 38

cytosol

Question 39

what do the calcium ions bind to once in the cytosol?

Answer 39

troponin on the actin filaments

Question 40

how is the myosin binding site exposed on the actin molecule

Answer 40

tropomyosin moves once calcium binds

Question 41

what happens when the actin myosin binding site is exposed?

Answer 41

myosin cross bridges bind to the actin and strokes forward pulling actin

Question 42

why do you get rigor mortis?

Answer 42

there is no energy to relax muscle

Question 43

what happens in isometric muscle contraction?

Answer 43

muscle stays at a constant length

Question 44

what are the different types of muscle contraction?

Answer 44

isometric, isotoinic and isokinetic

Question 45

what is isotonic muscle contraction

Answer 45

contraction against natural resistance

Question 46

what is isokinetic muscle contrction?

Answer 46

sports training

Question 47

what is concentric muscle contraction?

Answer 47

muscle shortens

Question 48

what is eccentric muscle contraction?

Answer 48

muscles may lengthen when contracting