What is the body's first line of defense against infection by foreign organisms?

The first line of defense against infection are the surface barriers. The surface barriers include intact skin, secretions of skin and mucous membrane. Skin protects external or outside boundaries and mucous membranes protect internal boundaries. Both the skin and mucous membranes release chemical secretions which restrict the growth of microbes on their surfaces if pathogens cannot cross the first line of defense body, they cannot disrupt normal functioning of and cannot cause disease.

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.