Sensory Receptors 2 Flashcards
What are 3 types of proprioceptors and their function?
Muscle spindles monitor muscle length and rate of change
Golgi tendon organs monitor tension on tendons
Joint receptors monitor joint angle and rate of angular movement
What 3 things to proprioceptors do?
Control voluntary movement
Send info for spinal cord reflexes
Send sensory information to perceive limb and body position
What is another name for “Send sensory information to perceive limb and body position”?
Kinaesthesia
Most contractile skeletal muscle fibres are ______ but there are some intrafusal muscle fibres with ______ sensory and motor innervation.
Extrafusal, specialised.
What do intrafusal muscle fibres form?
Muscle spindles which lie in parallel with muscle fibres.
______ motor neurons cause extrafusal muscle to contract and ______ motor neurons for intrafusal.
Alpha, gamma.
Define nuclear bag fibres.
Bag shaped and nuclei collected together.
Define nuclear chain fibres.
Nuclei lined up in a chain.
What nerves spiral round the centre of intrafusal fibres to form annulospiral endings?
Primary endings from Ia afferent nerves.
What nerves spiral round the centre of intrafusal fibres to form flower-spray endings?
Secondary endings from type II afferent nerves.
What do the ends of intrafusal fibres have that the centres don’t?
Contractile sarcomeres.
What happens when stretch sensitive channels open?
It creates a local generator potential, causing a regenerative action potential in afferent fibres.
What is joint movement organised by?
Groups of muscles working in opposition.
What do the nerve endings of golgi tendon organs mingle with?
Tendon bundles at the end of muscles.
Why doesn’t passive stretch affect tendons?
They are fairly inelastic.
