BIOL 3053 Lecture Notes - Lecture 9: Hiv, Influenza, Avian Influenza
Document Summary
Extremely small: too small to be seen with light microscope. Contain a single type of nucleic acid- dna or rna. Sometimes also an envelope of lipids, proteins and carbohydrates. Have few or no enzymes of their own- no enzymes for energy (atp) generation or protein synthesis. This is of medical importance in developing medical drugs. Most infect specific types of cells of one host. Rare cases cross host- range barrier (e. g. avian influenza (bird flu)) Virion- a complete, fully developed infectious viral particle. Composed of nucleic acid: genetic information, and surrounded by protein coat. Nuclei acid either dna or rna, never both (v. imp) Arrangement of capsomeres is a characteristic of a particular type of virus. Covers the capsid of some viruses (enveloped viruses) Some animal viruses acquire envelope from host plasma membrane when leaving the cell (budding) Can sometime be covered with spike- carbohydrate- protein complexes that project from the envelope surface.