week 1

Question 1

what is the fundamental functional unit of MU

Answer 1

contraction

Question 2

how is force controlled

Answer 2

1.altering the #
of active MUs (de/recruitment)
2.changing Frequency of activation
(rate coding – MU discharge rate)

Question 3

how are alpha motor neuron innervated

Answer 3

by its axon

Question 4

what does the myelin insulates the axon prevent

Answer 4

prevents movement of ions across a membrane

Question 5

why do action potential move one at a time

Answer 5

as they jump through the gaps of the myelin sheath

Question 6

what does the myelin sheath do

Answer 6

-increases conduction velocity without changes the axon diameter

Question 7

type 1

Answer 7

S motoneurons innervate SO type
muscle fibres forming S type motor units

Question 8

Type II MUs,

Answer 8

FR motoneurons innervate FOG
type muscle fibres forming FR type motor units

Question 9

Large motor neurons supply primarily

Answer 9

fast- twitch muscle fibers, small to
slow-twitch

Question 10

Input resistance:

Answer 10

small motor neurons (Type I) have high input resistance
(leads to greater response (easier to excite)