Nt1310 Lab 9
LAB 9: Skeletal Muscle Physiology
Electrical Stimulation
1. Complete the following statements by filling in your answers on the appropriate lines below.
A motor unit consists of a ___1___ and all the ___2___ it innervates.
Whole muscle contraction is a(n) ___3___ response.
A ___4___ is the response of a muscle to a single, brief threshold stimulus.
When the frequency of stimulation is so high that the muscle tracing shows fused peaks, ___5___ has been achieved.
___6___ is the stimulus strength at which the first observable muscle contraction occurs
The phenomenon, called ___7___, brings more and more muscle fibers into play
1. _motor neuron___
2. _muscle fibers___
3. _involuntary___
4. _Muscle …show more content…
As the total force increased, the active force ( increased / decreased ).
5. Explain what happens to muscle force production at extremes of length (too short or too long). (Hint: Think about sarcomere structure and actin and myosin interactions)
Muscle too short: _Muscle force produced is reduced and they lose their strength as they cannot contract.___
Muscle too long: _Muscle force production is reduced because of insufficient overlap of actin and myosin. There isn’t maximal cross bridge formation.___
Terms
6. Select the LETTER of the condition from column B that most correctly identifies the term in column A.
Column A Column B
__C__ 1. Muscle twitch
_E___ 2. Wave summation
_B___ 3. Multiple motor unit summation
__F__ 4. Resting length
_D___ 5. Resistance
_I___ 6.concentric isotonic contraction (shortening)
_H___ 7. Eccentric isotonic contraction (lengthening)
_A___ 8. Motor unit
_G___ 9. tetanus
A. Many cells responding to one neuron
B. Affects the speed of a muscle contration
C. A single contraction of intact muscle
D. Recruitment
E. The addition of one twitch to
Electrical Stimulation
1. Complete the following statements by filling in your answers on the appropriate lines below.
A motor unit consists of a ___1___ and all the ___2___ it innervates.
Whole muscle contraction is a(n) ___3___ response.
A ___4___ is the response of a muscle to a single, brief threshold stimulus.
When the frequency of stimulation is so high that the muscle tracing shows fused peaks, ___5___ has been achieved.
___6___ is the stimulus strength at which the first observable muscle contraction occurs
The phenomenon, called ___7___, brings more and more muscle fibers into play
1. _motor neuron___
2. _muscle fibers___
3. _involuntary___
4. _Muscle …show more content…
As the total force increased, the active force ( increased / decreased ).
5. Explain what happens to muscle force production at extremes of length (too short or too long). (Hint: Think about sarcomere structure and actin and myosin interactions)
Muscle too short: _Muscle force produced is reduced and they lose their strength as they cannot contract.___
Muscle too long: _Muscle force production is reduced because of insufficient overlap of actin and myosin. There isn’t maximal cross bridge formation.___
Terms
6. Select the LETTER of the condition from column B that most correctly identifies the term in column A.
Column A Column B
__C__ 1. Muscle twitch
_E___ 2. Wave summation
_B___ 3. Multiple motor unit summation
__F__ 4. Resting length
_D___ 5. Resistance
_I___ 6.concentric isotonic contraction (shortening)
_H___ 7. Eccentric isotonic contraction (lengthening)
_A___ 8. Motor unit
_G___ 9. tetanus
A. Many cells responding to one neuron
B. Affects the speed of a muscle contration
C. A single contraction of intact muscle
D. Recruitment
E. The addition of one twitch to