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.
Most floods in some parts of the world are caused by rapid spring snow melt or storms that bring heavy rains over a large region. More precipitation (rain, snow) than runoff results in local flooding. Agricultural and forestry practices can greatly affect the capacity of land to hold water.