The Stretch Reflex : (See Figure 13.15). The stretch reflex in its simplest form involves only 2 neurons, and is therefore sometimes called a 2-neuron reflex. The two neurons are a sensory and a motor neuron. The sensory neuron is stimulated by stretch (extension) of a muscle.
Flash floods are the most common flood type in normally-dry channels in arid zones, known as arroyos in the southwest United States and many other names elsewhere. In that setting, the first flood water to arrive is depleted as it wets the sandy stream bed.
Sinkholes occur worldwide; Texas is one of the U.S. âhot spotsâ for sinkholes. Structures built on limestone and sandstone bedrock can be especially vulnerable. Acidic water from rain and ruptured pipes can erode the bedrock, forming cavities. A sudden influx of rain after a dry period can trigger development of sinkholes.