PPT-Viral genetic mutation Viruses undergo genetic change by several mechanisms. These include

  Antigenic drift where individual bases in the DNA or RNA mutate to other bases Most of these point mutations are silent  they do not change the protein that the gene encodes . Chapters 12 and 13. Viral Characteristics and Structure. Why Viruses aren’t Alive. General Characteristics of Viruses. Name derives from the Latin for “poison”. Obligatory intracellular parasites. Other . Acellular. Infectious Agents. 1. 6. Copyright © McGraw-Hill Global Education Holdings, LLC. Permission required for reproduction or display.. Acellular. Agents. Viruses . – protein and nucleic acid. Introduction. A species of mockingbird lives in the Apalachicola National Forest. One year, a few of the mockingbirds were born with very long beaks. Over the next several years, the area experienced particularly cold winters. The weather forced the insects in the area to burrow deeper into the ground. Surveys of the mockingbird population showed that the number of long-beaked mockingbirds had increased. What would account for this increase in the number of long-beaked mockingbirds?. Viruses . A nonliving (?) particle made of proteins, nucleic acids, and sometimes lipids (fats). Viruses only reproduce by infecting living cells. Most viruses can only be seen with an electron microscope. VOCABULARY. Virus. Capsid. Envelope. Human . Immunodeficiency Virus (HIV. ). Influenza. Lytic Cycle. Lysogenic Cycle. Lysis. Retrovirus. Prerequisite questions. What are the eight characteristics which all living things have in common. Chapters 27 and 19. YOU MUST KNOW. The key ways in which prokaryotes differ from eukaryotes with respect to genome, membrane-bound organelles, size, and reproduction. How horizontal acquisition of genetic information occurs in prokaryotes via transformation, conjugation, and transduction. Where are cases of viral hemorrhagic fever found Taken together the viruses that cause VHFs are distributed over much of the globe However because each virus is associated with one or more particular . . The process of transfer of virus into host is referred as . TRANSMISSION. and this is an important step in the life cycle of viruses.. Person to person infections are said to be . HORIZONTAL. . (Chapter 12). Presented by Dr. Laurie M. Erickson. Chair of the Department of Health Sciences. Blitstein Institute of Hebrew Theological College. Chicago, IL, USA.. 12.1-12.2 Mutations . Mutation:. any heritable change in the genetic material. Viruses are acellular organisms. completely obligatory parasites. . The term virus means ‘poison’.. Most of them are disease causing . Have a complex mechanism of hijacking the machinery of the host genome for its self replication.. If the enzyme that converts tyrosine to melanin is defective, no melanin is produced and a genetic disease known as albinism results.. A peacock with albinism does not produce the melanin needed to make the bright colors of its feathers.. Learning Goal . Identify the type of change in DNA for a point mutation, a deletion mutation, and an insertion mutation. . Genetic Mutation. A. . mutation. is a change in the nucleotide sequence of DNA.. What is the viruses. Structure/classification of the viruses. Replication of the viruses. Out come of the viral infection . History. Through the 1800s, many scientists discovered that something smaller than bacteria could cause disease and they called it . Dr.Luma. . amer. Viral genetics. Viruses are simple . creatures, . lacking an . energy-generating system . and having very limited . biosynthetic capabilities. . The smallest viruses have only a . few genes.