spindle

spindle /spin·dle/ (spin´d'l)

1. a pin tapered at both ends.

2. the fusiform figure occurring during metaphase of cell division, composed of microtubules radiating from the centrioles and connecting to the chromosomes at their centromeres.

3. a type of brain wave occurring on the electroencephalogram in groups at a frequency of about 14 per second, usually while the patient is falling asleep.

4. muscle s.

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Krukenberg's spindle  a spindle-shaped, brownish-red opacity of the cornea.

mitotic spindle  spindle (2).

muscle spindle  a fusiform end organ arranged in parallel between the fibers of skeletal muscle and acting as a mechanoreceptor, being the receptor of impulses responsible for the stretch reflex.

Diagrammatic cross-section of a muscle spindle showing the intrafusal fibers and afferent and efferent endings.

nuclear spindle  spindle (2).

tendon spindle  Golgi tendon organ.

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spin·dle (spndl)

n.

1. A fusiform structure, usually composed of microtubules.

2. Mitotic spindle.

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spindle,

n muscle, a fusiform body lying parallel to and between muscle fibers. It is composed of a conspicuously smaller modified muscle fiber that has its own motor end plate to cause it to contract and its own special sensory end organs (the flower spray ending and the anulospiral ending) that send information to the central nervous system regarding the state of contraction of the main muscle body.

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spindle

1. mitotic spindle; the fusiform figure occurring during metaphase of cell division, composed of microtubules radiating from the centrioles and connecting to the chromosomes at their centromeres.

2. muscle spindle.

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muscle spindle

a mechanoreceptor found within a skeletal muscle; the muscle spindles are arranged in parallel with muscle fibers. They contain three to 10 small, striated muscle fibers (intrafusal fibers) contained within a capsule and supplied with specialized motor and sensory nerves. They respond to passive stretch of the muscle but cease to discharge if the muscle contracts isotonically, thus signalling muscle length. The muscle spindle is the receptor responsible for the stretch or myotatic reflex.

spindle wood, spindle tree

euonymuseuropaea.