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.
Introduction. Meiosis, the form of cell division unique to egg and sperm production, sets the stage for sex determination by creating sperm that carry either an X or a Y sex chromosome.his means that when the chromosomes of egg and sperm cells combine at fertilization, the embryo regains the normal diploid number. Meiosis mixes up the parental genes in two ways. First, the members of each chromosome pair come together and swap segments in a process known as crossing over, or recombination.