All the biological macromolecules contain carbon, hydrogen and oxygen. however, most do not contain nitrogen. the category that contains nitrogen are a) lipids. eliminate b) proteins. c) carbohydrates. d) unsaturated fats.

B) Proteins

Lipids and Carbohydrates only contain carbon, hydrogen, and oxygen.

Unsaturated fats are a type of monomer for lipids, meaning they as well are only made up of carbon, hydrogen, and oxygen.

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.

igneous rocks which formed by the crystallization of magma at the surface of the earth called extrusive rocks. they are characterized by fine-grained textures because the rapid cooling at or near the surface did not provide enough time for large crystals to grow.