Knee jerk reflex mechanism. Animation showing the neural and muscular basis of the knee jerk reflex. This diagnostic response consists of a sudden extension of the leg and is stimulated by a blow on a tendon just below the kneecap. As shown, the blow stimulates a sensory receptor in a muscle spindle located in the quadriceps muscle. This gives rise to a nerve signal (light blue) that reaches the spinal cord (shown in expanded cross-section at right) via the dorsal root ganglion. This triggers motor neuron cell bodies that send signals (orange and red) that result in the contraction of an extensor muscle and flexor muscle in the leg, causing the reflex jerk. For this animation with labels, see K004/2047. | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Biocosmos / Francis Leroy & Valentin Legrand |
Modell-Rechte: | nicht erforderlich |
Länge: | 22 Sekunden |
Seitenverhältnis: | 16:9 |
Restrictions: | - |