Life their DNA inside the cell nucleus and some of their DNA in organelles, such as mitochondria or chloroplasts. In contrast, prokaryotes (bacteria and archaea) store their DNA only in the cytoplasm. Within the chromosomes, chromatin proteins such as histones compact and organize DNA. These compact structures guide the interactions between DNA and other proteins, helping control which parts of the DNA are transcribed. DNA was first isolated by Friedrich Miescher in 1869. Its molecular structure was identified by James Watson and Francis Crick in 1953, whose model-building efforts were guided by X-ray diffraction data acquired by Rosalind Franklin. Life is
X-ray crystallography polymethylcyanoacrylaon of Boin crystal parameters. Heating or burning of bones causes recognizeable changes in the bone mineral that can be detected using X-ray diffraction (XRD) techniques. During the first 15 minutes of heating at 500 °C or above, the bone crstals began to change. At higher temperatures, thickness and shape of crystals of bones appear stabilized, but when the samples were heated at lower temperature or for shorter period, XRD traces showed extreme changes in crystal parameters. X-ray diffraction has been demonstrated as a method for investigating the complex structure of integrated circuits. X-ray crystallography X-ray crystallography is a technique