A2.3 Viruses Flashcards
A2.3.1 Relatively _____ features are shared by all viruses
Few
A2.3.1 Features shared by viruses
-Small, fixed size
-Nucleic acid (DNA or RNA) as genetic material
-A caspid made of proteins
-No cytoplasm
-Few or no enzymes
A2.3.2 Viruses are highly _____ in their shape and structure
Diverse
A2.3.2 Genetic material of viruses may be _____ or _____, which can be either single- or double-stranded
RNA, DNA
A2.3.2 Some viruses are enveloped in _____ and others are not enveloped
Host cell membrane
A2.3.2 Examples of viruses
Bacteriophage lambda, coronaviruses, HIV
A2.3.3 Viruses rely on a _____ for energy supply, nutrition, protein synthesis, and other life functions
Host cell
A2.3.3 Describe the phases in a lytic cycle using bacteriophage lambda as an example
A2.3.5 The diversity of viruses suggests _____
Several possible origins
A2.3.4 Describe the phases in a lysogenic cycle using bacteriophage lambda as an example
A.2.3.5 Viruses share an extreme form of _____ as a mode of existence, so the structural features that they have in common could be regarded as _____ evolution
Obligate parasitism, convergent evolution
A.2.3.5 The _____ is shared between viruses and living organisms
Genetic code
A2.3.6 Reasons for very rapid rates of evolution in some viruses
A2.3.6 Examples of rapid evolution of viruses
Influenza viruses and HIV
A2.3.6 Consequences for treating diseases caused by rapidly evolving viruses
A2.3 Guiding Q: How can viruses exist with so few genes?
A2.3 Guiding Q: In what ways do viruses vary?
A2.3 Linking Q: What mechanisms contribute to convergent evolution?
A2.3 Linking Q: To what extent is the natural history of life characterized by increasing complexity or simplicity?
