Ultraviolet radiation from the sun alters the dna of a skin cell. this skin cell rapidly divides, but the resulting cells no longer function properly as skin cells. even though they do not know what to do, they continue to divide uncontrollably. this is an example of the early stages of

1. loamy sand is about 80% sand with 10% clay and defined mostly by sand particles with some clay to provide structure and fertility. the sand particles are easily visible and the soil holds structure but breaks apart easily.

2. scott sand can improve his soil quality by incorporating more silt and organic matter into the soil. peat moss and organic matter can also be incorporated.

straight probes are used primarily for measuring flow as it is approaching the test area. its geometry allows the probe to be mounted so that it is in the direct line of airflow.