I'm being taught that: a muscle fibre spans the entire length of the muscle, from the originating tendon to the inserting tendon.
The question is, can a muscle fibre contract only partially? Say, if the fibre is 1m long, can only the first 10cm contract without the rest contracting?
Additonally, to help me understand better: When a neuron innervates a muscle fibre, does it do it only at one spot, or can a muscle fibre be innervated in several spots? Can several neurons innervate the same muscle fibre?