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1. a pin tapered at one end or both ends, or something with this shape.
2. the thin, tapering figure occurring during metaphase of cell division, composed of microtubules radiating from the centrioles and connecting to the chromosomes at their centromeres. Called also mitotic spindle.
3. muscle spindle.
mitotic spindle spindle (def. 2).
muscle spindle a mechanoreceptor found between the skeletal muscle fibers; the muscle spindles are arranged in parallel with muscle fibers, and respond to passive stretch of the muscle but cease to discharge if the muscle contracts isotonically, thus signaling muscle length. The muscle spindle is the receptor responsible for the stretch or myotatic reflex.
sleep s's bursts of activity of a particular waveform in the electroencephalogram in light or early sleep.
anatomy, pathology any fusiform cell or structure.
1. Biology A cytoplasmic network composed of microtubules along which the chromosomes are distributed during mitosis and meiosis.
2. Anatomy See muscle spindle.
anatomy, pathology Any fusiform cell or structure.
spindleA term used adjectivally in anatomy and referring to any elongated cell or structure pointed at both ends. Fusiform.
In anatomy and pathology, any fusiform cell or structure.