# origin

origin (or´i-jin)

1. The less movable of the two points of attachment of a muscle, that which is attached to the more fixed part of the skeleton. 2. The starting point of a cranial or spinal nerve. The former have two o.'s: the ental o. , deep o. , or real o. , the cell group in the brain or medulla, whence the fibers of the nerve begin, and the ectal o. , superficial o. , or apparent o. , the point where the nerve emerges from the brain. [L. origo, source, beginning, fr. orior, to rise]
o. of replication a sequence of the bacterial genome required for the initiating of a replicating fork by leading strand synthesis.

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