PPT-CHARACTERISTICS OF VIRUSES

Are Viruses Living or Nonliving Biologists consider viruses to be nonliving because Are not cells Do not grow or respond to their surroundings Cannot make food take in food or produce wastes. A . virus. is a small . infectious agent. that can replicate only inside the living cells of organisms. Most viruses are too small to be seen directly with a . microscope. . Viruses infect all types of organisms, from . 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. 1. A program that attaches itself to another . executable. (a . host program. ). Whenever the host program is executed, virus code is ran and it can make a copy of itself and infect other executables found in your memory or hard drive. What is a Virus?. Very small . Non-living particle. Made up of nucleic acid. . and proteins. Can only reproduce by infecting living cells. Do not carry out respiration, grow or develop. Structure. Viruses have an inner core which contains either RNA or DNA. Infectious Agents of Animals . and Plants. Chapter 14. What am I?. Structure and Classification of Animal Viruses. Classification of animal viruses. Taxonomic criteria based on. Genomic structure. DNA or RNA. HIV infected T-cell. Viral Structure. not . cells. small . infectious particles . w/. DNA or RNA enclosed . in a protein coat . (capsid). in . some cases. , a membranous envelope. Viral Genomes. genomes . Viruses Are Not Cells!. There are several structural and functional differences between cells and viruses. The structural differences include:. No nucleus. No cell membrane. No organelles. The functional differences include:. CLS 212: Medical Microbiology. History. Through the 1800s, many scientists discovered that something smaller than bacteria could cause disease and they called it . virion. (. Latin word- poison. ).. STRUCTURE. A core nucleic acid - DNA or RNA. Nucleic Acid surrounded by a protein, called a capsid.. CLASSIFICATION. By genomes: DNA viruses, RNA viruses or retroviruses . (any . of a group of RNA viruses that insert a DNA copy of their genome into the . Folder Title: . CxVirus. (. NoTP. ). Updated: April 12, 2017. See Chapter 3, Weinberg, 2. nd. Edition pages 71 to 102. Importance of Virology to. Cancer Biology and Cancer Medicine. Need to Control Potentially Infectious Exposure. What do viruses need to reproduce?. Other viruses. Host organisms. A nutrient medium. An enzyme solution. Which characteristic do viruses possess in common with living cells?. They contain a nucleus and organelles.. Embryonated. Egg. Viruses. Viruses do not fall in the category of unicellular . microorganism. They . are obligate intracellular parasites and lack the . machinery . necessary for protein and nucleic acid . EQ: Why are viruses considered to be non-
living?. Characteristics:. *Nonliving particles made of . nucleic acid. and a . protein coat . enlosed in a . capsid. shell... *In order to reproduce, all viruses must have a . arboviruses. ) are viruses that can be transmitted to man by arthropod vectors. . Arboviruses. belong to three families:. Togaviruses. . Bunyaviruses. e.g. . Sandfly. Fever. .. Flaviviruses. e.g. Yellow Fever, dengue, Japanese Encephalitis.