Muscle 6 Flashcards
What does protein synthsis depend on?
Activation of skeletal muscle
What is cachexia?
Weakness and or wasting due to chronic disease
What are the 4 components of skeletal muscle reflexes
- Sensory receptor
- Integrating centre
- Efferent neurons
- Effectors
What is a monosynaptic reflex?
A single synapse between the efferent and afferent neurons
What is a polysynaptic reflex
Two or more synapses -> both in CNS
What receptors let the brain know where limbs are?
Proprioceptors
What are skeletal muscle reflexes initiated by (mostly)
Proprioceptors
What do joint receptors play a key role in
Proprioception
What are joint receptors for?
They provide information to the brain about angles or positions of joints -> which helps coordinate balance and posture
What does muscle spindle reflex do?
Helps maintain muscle tone and protect muscles from excessive stretching
What does alpha gamma coactivation do?
Maintains spindle function when muscle contracts
What are the 3 types of proprioceptors?
Intrafusal muscle spindle
Golgi tendon organ
Joint receptors
What is a muscle spindles role?
Send information to CNS about changes in muscle length
What are the contractile ends of intrafusal muscle spindles innovated by?
Gamma motor neurons
What does it mean that muscle spindles are tonically active?
They’re always firing action potentials back to the CNS
Where do muscle spindle reflexes go through?
Spinal cord so it is very fast
What 2 proprioceptors can drive skeletal muscle reflexes?
Muscle spindles and Golgi tendon organ
What do Golgi tendon organs respond to?
Muscle tension
What do Golgi tendon organs respond to?
Muscle tension
Does human muscle fibre increase during muscle hypertrophy ?
No → myofibrils do
What is reciprocal inhibition?
The antagonist muscle is inhibited and the other is contracted (one contracts while the other needs to be relaxed)
What are nociceptors?
Sensory neurons that sense pain and tissue damaging stimuli
What are flexion reflexes?
They pull limbs away from painful stimuli
What sensory neuron can drive skeletal muscle reflexes
Nociceptors
What is the crossed extensor reflex
A flexion reflex in one limb causes extension in the opposite limb → supports body as weight shifts away from painful stimulus
