PPT-Transmission Of viruses Viruses are intracellular parasites and have to find a new host

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 . Intro to viruses. http://www.brainpop.com/health/diseasesinjuriesandconditions/viruses. /. What is a Virus?. Very small . Non-living particle. Made up of nucleic acid. . and proteins. Can only reproduce by infecting living cells. 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 . M. acroparasites. & . M. icroparasites. CfE. . Advanced Higher Biology. Unit . 2: . Organisms and Evolution. SQA mandatory key area. Macroparasites. : . endoparasitic. amoebas, . platyhelminths. behaviour: . macroparasites. . & . microparasites. CfE. . Advanced Higher Biology. Unit . 2: . Organisms and Evolution. SQA . mandatory key area. Macroparasites. : . endoparasitic. amoebas, . platyhelminths. Draw the basic structure of a virus. Label and define capsid, viral envelope and nucleic acid.. Ch. 17 Warm-up. Draw the lytic/lysogenic cycle.. What stage of the lytic-lysogenic cycle is a virus virulent? Temperate?. Viruses consist of a nucleic acid (either DNA or RNA) associated with proteins encoded by the nucleic acid. The virus may also have a lipid . bilayer. membrane (or envelope) but this is acquired from the host cell, usually by budding through a host cell membrane. If a membrane is present, it must contain one or more viral proteins to act as . use many of the host cell’s biochemical mechanisms and products to sustain their viability. A mature virus(virion) can exist outside a host cell and still retain its infective properties.. . 3. the virus. (Assistant Professor). College of Fisheries, . Kishjanganj. BASU, Patna. Characteristics of viruses. Viruses may be regarded as . exceptionally complex aggregations . of . nonliving chemicals . or . exceptionally simple living microbes. & . M. icroparasites. CfE. . Advanced Higher Biology. Unit . 2: . Organisms and Evolution. SQA mandatory key area. Macroparasites. : . endoparasitic. amoebas, . platyhelminths. , nematodes. . Ectoparasitic. BCH 4I4. LECTURE 7-9. Survey of structural properties of different classes of viruses . S.O Anadozie (Ph.D. .). VIRUSES. A virus is a small filterable and obligate intracellular parasite requiring a living host for its multiplication . Viruses are the most primitive microorganisms infecting man. . General properties. Obligate intracellular . Possess either DNA (deoxyribonucleic acid) or RNA (ribonucleic acid), but never both . Smaller than bacteria, can be passed through the bacterial filters. . . . In order not to die out, viruses must be propagated and transmitted to new hosts in which more . virions. can be produced. The only other way for the survival of virus genes is to be maintained as in cells as nucleic acids, which are replicated and passed on to daughter cells when the cells divide. .