Proprioceptors are sense receptors embedded in muscle. A special category of proprioceptors are stretch receptors (also called muscle spindles), specialized muscle cells containing 1a sensory neurons in the central region. 1A sensory neurons are the first part of a reflex arc forming synapses in the spinal cord with alpha motor neurons which enervate the very muscle in which the spindle is located. Additionally, there are gamma motor neurons that act directly on the spindle. Under the influence of motor centers in the brain or reflex circuits, gamma neutrons initiate the reflex arc, 'tricking' the muscle through its spindle into contraction.
The WikiPremed MCAT Course is a comprehensive course in the undergraduate level general sciences. Undergraduate level physics, chemistry, organic chemistry and biology are presented by this course as a unified whole within a spiraling curriculum. Please read our policies on Privacy and Shipping & Returns. Contact Us. MCAT is a registered trademark of the Association of American Medical Colleges, which does not endorse the WikiPremed Course. WikiPremed offers the customers of our publications or our teaching services no guarantees regarding eventual performance on the MCAT.
WikiPremed is a trademark of Wisebridge Learning Systems LLC. The work of WikiPremed is published under a Creative Commons Attribution NonCommercial ShareAlike License. There are elements of work here, such as a subset of the images in the archive from WikiPedia, that originated as GNU General Public License works, so take care to follow the unique stipulations of that license in printed reproductions.