Muscles DD Flashcards
1
Q
What are the 3 sources of ATP replinishment for muscle contraction
A
Creatine phosphate
Glycogen
Cellular respiration
2
Q
Muscle Spindle
A
- Sensory receptors within the belly of a muscle
- Detect changes in length of muscle
3
Q
What 2 sensory organs “fine tune” muscle tone
A
Muscles spindles
Golgi tendon organs
4
Q
Muscle spindles groups and components detect and action
A
- Groups Ia and II afferents
- Components (highly differentiated)
- Specialized muscle fibers (encapsulated intrafusal fibers) runs parallel to extrafusal
- Sensory terminals (group Ia and II afferents)
- Motor terminals ( gamma motor (effernt) neurons)
- Detect static and dynamic changes in length
- Activate alpha motor neuron when stretched
5
Q
Golgi tendon organs
group
arrangement
detect
action
A
- Group Ib afferents
- Arranged in series, with extrafusal muscle fibers
- Detect muscle tensiom
- INHIBITS alpha motor neuron
6
Q
Stretch reflex
AKA Myotatic reflex
A
- Sensory receptors=Propioceptors
- Muscle stretch detected by muscle spindles which then depolarize
- Sends AP signal to spinal cord
- Synapses with motor neurons
- Triggers stretch reflex
- Muscle contracts
- Antagonistic muscles of contracting muscle are inhibited
- Called recipricol inhibition, through recipricol innervation
7
Q
Stretch reflex
synapses
Stimulus
Afferent fibres
Response
A
- Monosynaptic
- Muscle stretched
- Ia
- Responds by contracting
8
Q
Golgi tendon reflex
synapses
stimulus
fibers
response
A
- Disynaptic
- Muscle contraction
- Ib
- Responds by relaxing muscle
9
Q
Flexor withdrawal reflex
synapse
Stimulus
Fibers
Response
A
- Polysynaptic
- Pain
- II, III, IV
- Ipsilateral flexion, contralateral extension
10
Q
Reflex arc response
A
- Receptor at end of sensory neuron reacts (finger on stove)
- Sensory Afferent neuron conducts impulse
- Integration center 1 or more synapses in CNS
- Motor efferent neuron send impulse
- Effector responds by contracting
11
Q
Extrafusal fibers
A
- Fibers that make up bulk of muscle
- Innervated by alpha-motor neurn (effernt)
- Provide force for contraction
12
Q
Intrafusal fibers general
A
- Encapsulated in sheaths to form muscle spindles
- Innervated by gamma-motor neurons
- Run parallel to extrafusal
- too small to generate significant force
13
Q
Nuclear bag fibers
A
- An intrafusal fiber
- Detect fast, dynamic changes in muscle length and tension
- Innervated by grp Ia (fastest in body)
- Larger than chain
- Have nuclei in a central bag region
14
Q
Nuclear chain fibers
A
- Detect static changes in muscle length and tension
- Innervated ny slower grp II afferents
- Smaller and more numerous than nuclear bag fibers
- Nuclei are arranged in rows
