Obviously, the patellar reflex as such has no utility; no selective advantage is bestowed on animals that kick a limb when a tendon is tapped. However, if a more natural stimulus is applied, the utility of this mechanism becomes apparent. Figure 8.5 shows the effects of placing a weight in a person’s hand. This time I have included a piece of the spinal cord, with its roots, to show the neural circuit that composes the monosynaptic Stretch reflex. follow the circuit: Starting at the muscle spindle, affer_impulses are conducted to terminal buttons in the gray matter of the spinal cord. These terminal buttons 1 synapse on an alpha motor neuron that innervates the extrafusal muscle fibers of the same muscle. Only one synapse is encountered along the route from receptor to effector-hence the term monosynaptic. (See Figure 8.5.)