Exam and Actual Answers.
A motor unit includes: - Answer A.) Multiple muscle fibers innervated by multiple motor
neuron.
B.) One muscle fiber innervated by multiple motor neuron.
C.) Multiple muscle fibers innervated by one motor neuron.
D.) One muscle fiber innervated by one motor neuron.
Answer: C.)
Skeletal muscles are attached to bones of the skeleton by _________ - Answer Tendons
Each muscle is made up of many individual muscle fibers organized in - Answer Fascicles
What are the two methods of EMG recording? - Answer 1. Intramuscular: insert needle
electrodes through the skin into the muscle for an intramuscular EMG
2. Place electrodes on the skin surface for a surface EMG
Motor units fire _________________ - Answer asynchronously
EMG is a recording of: - Answer A.) The action potential of the motor nerves supplying the
muscle fibers.
B.) The contraction forces of the innervated muscle fibers.
C.) The action potentials of the innervated muscle fibers.
Answer: C.)
EMG testing is performed with another test, called a nerve conduction study, which yields
information on nerve function. What are the other tests? - Answer In conjunction with EMGs,
these tests can help with the diagnosis of nerve compression or injury (such as carpal tunnel
syndrome), nerve root injury (such as sciatica), and other problems of the muscles or nerves
Signal of interest must ______________________ - Answer Go through amplification,
filtering, sampling and display and if instead of being electrical is must be converted into analog
, Digital --> Analog
What is a transducer? - Answer Convert analog signal to digital signal
Powerlab hardware is able to: - Answer -- Convert analog signal to digital signal
-- Amplify a signal
-- Filter a signal
Integration ____________ - Answer Sums up raw EMG signal
Reciprocal activation: - Answer is simultaneous activation of an agonist muscle and inhibition
of an antagonist muscle
Each individual muscle fiber is innervated by a branch of an axon from a _______________ -
Answer Motor neuron
Skeletal muscle initiation by action potentials in motor neurons are under __________ - Answer
Voluntary control
When APs are generated, it _________ all of the muscle fibers innervated by that motor neuron
- Answer A.) inactivates
B.) depolarizes
C.) activates
D.) contracts
Answer: C.)
Motor unit: - Answer the motor neuron, together with all of the individual muscle fibers that
it innervates
EMG is a technique used for: - Answer the electrical activity of muscles
EMG is also known as: - Answer electromyogram