To prepare for this post we found ourselves chuckling about the antiquated duplicators of our childhood. In early primary grades our teachers used the ditto machine. Most copies were produced with a purple pigment. Fresh copies provided students with a captivating odor generated by the solvent used in the copying process. Perhaps my parents also used ditto worksheets. Ditto technology originated in 1910. One generation earlier my grandparents may have used practice sheets generated on a cutting edge mimeograph machine developed in 1884. A few years earlier carbon paper had made its debut and worked well with the advent of the typewriter in the 1870s.
Fast forward to the first years in my teaching career. My district provided the ditto machine for the production of classroom copies. Our school office used the difficult-to-use mimeograph machines. It produced many more copies at one sitting. Finally, in the early 1960s a close friend, using the newest equipment, produced multiple copies for me using a new Xerox copier at her place of employment. Cutting edge technology had finally provided the Xerox office printer with its ability to duplicate hundreds of copies cheaply and quickly. In a manner of speaking, the invention seemed “miraculous.” A century earlier hand copying was the only choice available.
In 1860, the year my maternal grandfather was born, the world of science knew nothing about a duplication method that all living materials had used since the creation of life. We speak of
DNA--the genetic blueprint which preserves every physical feature of every living thing. It is found in virtually every cell of all creatures. On average the unraveled DNA molecule in each microscopic human cell is 2m long. Each DNA molecule has 3.2 billion base pairs, groups of molecules that function as a code for regulating the body and producing RNA which directs the fabrication of every tissue of the body from thousands of proteins. The total length of human DNA in all cells would reach from the earth to the sun and back multiple times.
Understanding the copying mechanism of
DNA inspires deep reverence for the Creator. DNA information is copied to each cell as the body grows. When living things reproduce, the DNA preserves and passes on inheritance to the next generation. The fixity of species for uncounted millennia is testimony to the faithfulness of the copying mechanism. The copying mechanism of living things puts to shame the modern office technology I earlier pronounced “seemingly miraculous.” In reality, the various copying strategies of the machines in our offices and homes provide no legitimate comparison with the majesty of DNA.
The stranded double helix
DNA molecule is able to “unstrand” at an appropriate time. An AP text, Biology, by Campbell and Reese, states “The two strands of the double helix are complementary, each the predictable counterpart of the other. It is this feature of DNA that makes possible the precise copying of genes that is responsible for inheritance. In preparation for cell division, each of the two strands of a DNA molecule serves as a template to order nucleotides into a new complementary strand. The result is two identical copies of the original double-stranded DNA molecule, which are then distributed to the two daughter cells. Thus, the structure of DNA accounts for its function in transmitting genetic information whenever a cell divides.”
We expand on our earlier statement that the various copying strategies of the machines in our offices and homes provide no legitimate comparison with
DNA. Office machines copy information on a two-dimensional sheet of paper, but duplication of DNA results in a three-dimensional molecule identical to the original. Therefore, not only is the information duplicated, but so also is the structure. The stage is now set for discovering more wonderful processes beyond the role of DNA in future posts. The processes are summarized (1) DNA makes RNA, and (2) RNA makes protein. The hundreds of pages describing these processes in biology texts attest to the magnificence of God’s creation at the level of the micro cosmos.