What is biliary atresia? Biliary atresia is a relatively rare disease that begins in early infancy and affects about one in every 10,000 to 20,000 infants. In biliary atresia the bile duct that leads from the liver to the intestine becomes damaged preventing bile from leaving the liver. In the early stages the bile duct outside the liver is mainly affected, but in later stages bile ducts inside the liver are also damaged.
Section 6.3 Viruses: Structure, Function, and Uses. A virus is a small parasite that cannot reproduce by itself. Once it infects a susceptible cell, however, a virus can direct the cell machinery to produce more viruses. Most viruses have either RNA or DNA as their genetic material.The nucleic acid may be single-or double-stranded.he T phages of E. coli are large lytic phages that contain a single molecule of double-stranded DNA. This molecule is about 2âÃâ10 5 base pairs long in T2, T4, and T6 viruses and about 4âÃâ10 4 base pairs long in T1, T3, T5, and T7 viruses.
DNA (deoxyribose nucleic acid) has been found to be a genetic material in all the living beings except few plant viruses where RNA is the genetic material because DNA is not found in such viruses.