The nitrogen oxides are not all bad. They are both used in the lead chamber process as catalysts to convert SO2 to SO3, which is the essential first step in the production of sulphuric acid. They are also precursors in the Ostwald Process for the manufacture of nitric acid (see below).
Single Gene Traits in Humans. The following is a list of some autosomal human traits that have been attributed to a single gene. Although clearly other genes are involved, the inheritance of each of these phenotypic traits acts as if it were governed by a single gene. First, indicate your expression of the trait (i.e., circle the appropriate phenotype).
More than one gene determines these traits, with each gene giving a small, yet additive effect. Multifactorial traits do not exhibit Mendelian ratios, and are determined between genes, or a gene, and the environment. A pure polygenic trait that is free of any environmental influence are rare.