Sensory Receptors : Proprioception Flashcards
<p>What is a proprioreceptor?</p>
<p>A proprioreceptor is a mechanoreceptor that signals the bodies or limbs position</p>
<p>What are examples of proprioreceptors?</p>
<p>Examples of proprioreceptors are:</p>
<p>Muscle spindle</p>
<p>Golgi tendon organs</p>
<p>Joint receptors</p>
<p>What does the muscle spindle do?</p>
<p>The muscle spindle monitors the muscle length and rate of change of muscle length</p>
<p>Controls reflexes and voluntary movement</p>
<p>What does the golgi tendon organ do?</p>
<p>The golgi tendon organ monitors the tension on a tendon</p>
<p>What does a joint receptor do?</p>
<p>A joint receptor monitors the joint angle, rate of angular movement and the tension on the joint</p>
<p>What are the three things that proprioreceptors do?</p>
<p>Allow the brain to control voluntary movement by sending sensory information</p>
<p>Muscle spindle and golgi tendon organs give sensory information that drives spinal cord reflex</p>
<p>Percieve limb and body position and movement in space (kinaesthesia)</p>
<p>What is the muscle spindle composed of?</p>
<p>The muscle spindle is composed of intrafusal and intrafusal muscle fibres</p>
<p>What are the intrafusal muscle fibres contained in?</p>
<p>Intrafusal muscle fibres are contained in a capsule and have their own sensory and motor innervations</p>
<p>Lie parralel to muscle fibre</p>
<p>How do intrafusal muscles lie in relation to the muscle fibres?</p>
<p>Lies parralel</p>
<p>What does the alpha motor neuron do?</p>
<p>The alpha motor neuron goes to the extrafusal muscle fibre and makes it contract</p>
<p>What does the gamma motor neuron do?</p>
<p>The gamma motor neuron goes to the intrafusal muscle fibre at each end</p>
<p>What are the two types of intrafusal fibres?</p>
<p>The two types of intrafusal fibres are:</p>
<p>Nuclear bag fibre</p>
<p>Nuclear chain fibre</p>
<p>What are nuclear bag fibres?</p>
<p>Nuclear bag fibres are bag shaped with nuclei collected together</p>
<p>What are nuclear chain fibres?</p>
<p>Nuclear chain fibres are nuclei lined up in a chain</p>
<p>Are muscle fibres multi or mono nucleic?</p>
<p>Muscle fibres are multinucleic</p>
What does a diagram showing the contractile and non contractile end of a muscle fibre look like?
<p>What are the two ends of a intrafusal muscle fibre innervated by?</p>
<p>Gamma fibres</p>
<p>What part of the intrafusal muscle fibre contracts?</p>
<p>The ends, not the middle</p>
<p>What are annulospiral endings?</p>
<p>Primary endings from type I alpha afferent nerves wrap around centre of the intrafusal fibre</p>
<p>What are flower spray endings?</p>
<p>Secondary endings from type II afferent</p>
<p>What happens when the gamma fibre fires?</p>
<p>Ends contract and shorten</p>
<p>Middle stretches</p>
<p>What stimulates the spindle stretch receptors?</p>
<p>The muscle stretching</p>
<p>What happens when a stretch stimulates the spindle stretch receptors?</p>
<ol> <li>Stretch sensitive ion channels open</li> <li>Causes generator potential</li> <li>Causes action potential</li></ol>
<p>What does the resting action potential depend on during a stretch?</p>
<p>The length Lo</p>
<p>What does the action potential frequency depend on during a stretch?</p>
<p>The velocity of the stretch from L0to L1</p>
<p>What happens to the action potential frequency after the stretch?</p>
<p>After a stretch the action potential frequency is at a new steady state (L1> L0)</p>
<p>What is joint movement organised by?</p>
<p>Joint movement is organised by groups of muscles working opposite to each other</p>
<p>What is a relationship around a joint between the agonist and the antagonist?</p>
<p>When the agonist contracts the antagonist relaxes</p>
<p>What does contracting a muscle mean?</p>
<p>Shortening the muscle</p>
<p>What does the golgi tendon organ do (GTO)?</p>
<p>The golgi tendon organ monitors muscle tension</p>
<p>What is the relationship between the golgi tendon organ and the tendon?</p>
<p>Nerves endings of the golgi tendon organ mingle with tendon bundle at the end of the muscle, so they monitor the stretch of the tendon</p>
<p>How do passive stretches affact the tendon?</p>
<p>Passive stretches do not effect the tendon much unlike muscle spindle because they are inelastic</p>
<p>How do muscles develop tension?</p>
<p>By contracting to stretch the tendon</p>
<p>What happens to the tension in a tendon when a muscle fibre contracts?</p>
<p>It increases the tension</p>
<p>How does the muscle spindle and the golgi tendon organ lie in relation to the extrafusal muscle fibre?</p>
<p>Muscle spindle lies parralel and the golgi tendon organ lies in series</p>
<p>What is the function of the gamma motor neuron?</p>
<p>Contract the poles of the muscle spindle so it matches the muscle</p>
<p>Where do the alpha and gamma neurons connect to?</p>
<p>Alpha goes to the muscle</p>
<p>Gamma goes to the muscle spindle</p>
<p>What happens to the gamma motor neuron when the alpha is activated?</p>
<p>Alpha is activated to cause contraction</p>
<p>Gamma is activated in parralel to maintain spindle selectivity (tension matches new muscle length)</p>
<p>What is an example of proprioreceptors acting autonomically?</p>
<p>Controlling movement such as the spinal cord reflex</p>
