Allergies result when the immune system: responds to harmless nonself molecules and cells. responds to self molecules and cells. responds to harmful nonself molecules and cells. does not respond to self molecules and cells.

Allergies result when the immune system: responds to harmless nonself molecules and cells.

Allergies occur when the immune system makes inflammatory responses to harmless antigens. Common causes include pollens, dust mites, molds, some foods like peanuts, insect stings, and a few medications.

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.

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.