THE POLYMERASE CHAIN REACTION (PCR) OBTECTIVE: To amplify a region of ribosomal DNA from a small amount of genomic DNA. INTRODUCTION: The polymerase chain reaction (PCR) was developed in 1983 by Kary Mullis, a nucleic acids chemist (then at Cetus).HE POLYMERASE CHAIN REACTION (PCR) OBTECTIVE: To amplify a region of ribosomal DNA from a small amount of genomic DNA. INTRODUCTION: The polymerase chain reaction (PCR) was developed in 1983 by Kary Mullis, a nucleic acids chemist (then at Cetus).
The elements on the periodic table are divided in three categories which are metals, non-metals and metalloids. Metals and nonmetals are two categories that are used to classiâ¦fy  the elements in the periodic table. The third is inert gases. 7 people found this useful.
Elements that lie in the same column on the periodic table (called a group) have identical valance electron configurations and consequently behave in a similar fashion chemically. For instance, all the group 18 elements are inert, or noble gases.lement groups are either nonmetals or various subsets of metals, but there is no distinct line between the two types of elements. Metal elements are usually good conductors of both electricity and heat. Subsets are based on similar characteristics and chemical properties.