Coin grading. Coin grading is the process of determining the grade or condition of a coin, one of the key factors in determining its value. A coin's grade is generally determined by five criteria: strike, preservation, luster, color, and attractiveness. Several grading systems have been developed. Certification services professionally grade coins for tiered fees.
DNA is composed of repeating units called nucelotides or nucleotide bases. DNA polymerase is responsible for the process of DNA replication, during which a double-stranded DNA molecule is copied into two identical DNA molecules.NA polymerase / DNAP. DNA polymerase (DNAP) is a type of enzyme that is responsible for forming new copies of DNA, in the form of nucleic acid molecules. Nucleic acids are polymers, which are large molecules made up of smaller, repeating units that are chemically connected to one another.
The mechanism of transcription has parallels in that of DNA replication. As with DNA replication, partial unwinding of the double helix must occur before transcription can take place, and it is the RNA polymerase enzymes that catalyze this process.ranscription is the process by which DNA is copied (transcribed) to mRNA, which carries the information needed for protein synthesis. Transcription takes place in two broad steps. First, pre-messenger RNA is formed, with the involvement of RNA polymerase enzymes.