Rheumatoid Arthritis Symptoms In Women. Disorder that is believed to result from an autoimmune process in which the body's immune system attacks itself. It is a system-wide disease that usually last for many years. In some patients, RA affects such organs as the heart, lungs, and eyes.
The first organic molecules formed about 4 billion years ago. This may have happened when lightning sparked chemical reactions in Earthâs early atmosphere. RNA may have been the first organic molecule to form as well as the basis of early life. Explore More Use the time slider in this resource to answer the questions that follow.
Watson and Crick describe structure of DNA1953. Photo: Model of DNA molecule. In the late nineteenth century, a German biochemist found the nucleic acids, long-chain polymers of nucleotides, were made up of sugar, phosphoric acid, and several nitrogen-containing bases.Later it was found that the sugar in nucleic acid can be ribose or deoxyribose, giving two forms: RNA and DNA.atson and Crick describe structure of DNA1953. Photo: Model of DNA molecule. In the late nineteenth century, a German biochemist found the nucleic acids, long-chain polymers of nucleotides, were made up of sugar, phosphoric acid, and several nitrogen-containing bases.