Chapter 6 viruses 6. 1 General Properties of Viruses 6.2 Structure of viruses 6.3 The cultivation of viruses 6. 4 General Features of Virus Reproduction 6. 5 one-step growth curve 6.6 Temperate Bacteriophages: Lysogeny and Lambda 6.7 viral classification 6.8 Overview of animal viruses 6.9 plant viruses 6.10 Viroids and Prions
6.1 General Properties of Viruses 6.2 Structure of viruses 6.3 The cultivation of viruses 6.4 General Features of Virus Reproduction 6.5 one-step growth curve 6.6 Temperate Bacteriophages: Lysogeny and Lambda 6.7 viral classification 6.8 Overview of Animal Viruses 6.9 plant viruses 6.10 Viroids and Prions Chapter 6 Viruses
TThe viruses Introduction and general characteristics Virus: simple, acellular entities consisting of one or more molecules of either DNA or RNa enclosed in a coat of protein. They are reproduced only within living cells and are obligately intracellular pa arasites The nucleic acid strands can be linear, closed cycle, or able to assume either shape A virus particle containing nucleic acid surrounded by protein and other macromolecular components Is called virion Viruses have a heavy dependence on host-cell structural and metabolic components Viruses can confer important new properties on their host cell
The Viruses Introduction and general characteristics • Virus : simple, acellular entities consisting of one or more molecules of either DNA or RNA enclosed in a coat of protein. They are reproduced only within living cells and are obligately intracellular parasites • The nucleic acid strands can be linear, closed cycle, or able to assume either shape • A virus particle containing nucleic acid surrounded by protein and other macromolecular components is called virion. • Viruses have a heavy dependence on host-cell structural and metabolic components. • Viruses can confer important new properties on their host cell
6.1 General Properties of viruses Viruses differ from living cells in at least three ways: (1) their simple, acellular organization (2)the absence of both dna and rna in the same vIrion, 3)their inability to reproduce independently of cells and carry out cell division as prokaryotes and eukaryotes do
(1) their simple, acellular organization (2) the absence of both DNA and RNA in the same virion, (3) their inability to reproduce independently of cells and carry out cell division as prokaryotes and eukaryotes do. Viruses differ from living cells in at least three ways: 6.1 General Properties of Viruses
Viruses can exist in two phases extracellular and intracellular The extracellular phase. posses few if any enzymes and can not reproduce independently of living cells In the intracellular phase, viruses exist primarily as replicating nucleic acids that induce host metabolism to synthesize virion components; eventually complete virus particles or virions are released
The extracellular phase, posses few if any enzymes and can not reproduce independently of living cells. In the intracellular phase, viruses exist primarily as replicating nucleic acids that induce host metabolism to synthesize virion components; eventually complete virus particles or virions are released. extracellular and intracellular Viruses can exist in two phases
Hosts and size Three main classes -animal viruses, bacterial viruses (bacteriophages), and plant viruses. The particular host range of a virus is determined by the virus's requirements for its specific attachment to the host cell and the availability within the potential host of cellular factors required for viral multiplication
Hosts and size Three main classes - animal viruses, bacterial viruses (bacteriophages), and plant viruses. The particular host range of a virus is determined by the virus's requirements for its specific attachment to the host cell and the availability within the potential host of cellular factors required for viral multiplication