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What is which of the following is true regarding nuclear bag fibres of motorunit ? and explain in detail?
Two types of intrafusal fibres -- nuclear bag fibre * primary (la) afferent -- supplies annulospiral ending in the centre -- provide information on muscle length and velocity (phasic response) fast stretch reflex -- nuclear chain fibre * primary (la) and secondary (II) afferent -- supplies flower spray ending -- monitor the length of the muscle (tonic response) --slow stretch reflex ref : guyton and hall