spinal reflexes Flashcards
what is a reflex?
any response that occurs automatically without conscious effort
what is an example of an everyday reflex?
-touching a hot plate
-the person docent know the plate is hot and immediately pulls their hand away
what is a monosynaptic reflex?
a monosynaptic reflex involves only one synapse between sensory and motor neurons.
what is a polysynaptic reflex?
A polysynaptic reflex is a type of reflex arc in which signals travel across multiple synapses (connections between neurons) before producing a response
what are the components of a reflex arc?
-stimulus
-sensory / afferent neuron
-integration centre
-motor / efferent neuron
-effector - muscle
what are 3 examples of sensory receptors?
-exteroceptors
-proprioceptors
-interoceptors
describe exteroceptors
-located on the skin and sense organs
-they respond to external stimuli
-carry info about temp, pressure etc
describe proprioceptors
these receptors are located in muscles eg muscle spindles, tendons and joints
-send information about position of the muscle eg length of muscle, tension
describe interoceptors
-sensory receptors on the internal organs
-send info about pain, stretching of internal organs
what are the 2 main sensory receptors located on muscles and tendons?
-muscle spindles
-golgi tendon organs
what do muscle spindles carry info about?
length / rate of change in length of muscle
what do Golgi tendon organs carry info about?
-tension/ rate of change of tension in muscle / tendon
what id the area for integration in the CNS in a reflex arc?
-brain or spinal cord receives , processes and integrates incoming sensory info and then issues command to effectors
what are the functions of the spinal cord in relation to the reflex arc?
-link for transmission between brain and PNS
-integrates reflex activity between afferent input and efferent output without involving the brain
how do afferent sensory fibres enter the spinal cord & where are their cell bodies located??
through the dorsal root
-CB’s located in the dorsal root ganglion
what are the effectors in the reflex arc?
-the organs which respond by doing something ie executing the response
-in somatic NS - effectors are skeletal muscle and in the ANS the effectors are cardiac, smooth muscle etc