Serratia marcescens is normally associated with nosocomial infections like catheter-associated bacteremia. In hospitalized adults, it is very common in urinary tract infections and sometimes in wound infections. Diagnosis in children often find the disease in the gastrointestinal system.erratia Marcescens symptoms are commonly associated with urinary tract infections, but in 30% to 50% of reported cases, there are no symptoms to assist diagnosis.
The joining. of an egg and a sperm is called fertilization, and the cell that. forms is called a zygote (ZI goht). Generally, the egg and the. sperm come from two different organisms of the same species. Following fertilization, mitosis and cell division begins. A new. organism with a unique identity develops.
The cells that form human eggs begin meiosis while the mother is herself still an embryo in the womb. But meiosis stops in the middle of prophase I, before birth, and does not resume until after the egg is released from the ovaries from 13 to 55 years later. Nondisjunction of chromosome 21 may be the result of interrupting the complicated process of meiosis for so long time.