acidophiles live at low pH Archaea are more abundant and widespread than

Acidophiles live at low ph archaea are more abundant

This preview shows page 2 - 5 out of 15 pages.

acidophiles (live at low pH) Archaea are more abundant and widespread than previously thought present in vast numbers in soil and in ocean associate with many animals Methanogens archaea that produce methane (natural gas)
Image of page 2
Obligate anaerobes (can only grow in environments that lack oxygen) Very abundant in the environment Eukaryote membrane bound nucleus can be unicellular, colonial, or multicellular reproduction is asexual or sexual many eukaryotes are microbial microbial protists any eukaryote that isn't animal, fungus, or plant Algea: photo-autotrophic protist disease causing protists Phytophthora infestans the plant destroyer, cause of late blight an oomycete cause of the irish potato famine Giardia lamblia (in intestines) Toxoplasma ghandi 6-8 main lineages of Eukaryotes Most are protists and all lineages contain at least some protists Fungi more closely related to animals than to the rest of the Eukaryotes Absorptive heterotrophs (absorb nutrients throughout cell membrane) often Saprobes that recycle organic material can be unicellular or multicellular Yeasts: single cells Filamentous Fungi: mycelial Dimorphic fungi: have both yeast and mycealial forms reproduce via spores important for biotechnology, food production, and disease Unicellular Fungi Saccharoyces cerevisiae: yeast used for bread and beer Candida albicans: yeast that can infect people with compromised immune systems Filamentous Fungi grows with chains of grows with a chains of cells called hyphae Ex: molds, and mildews, mushrooms disease fungi are a common cause of disease Ex: Chytrid fungi infects amphibians Microscopic animals Ex: dust mite, nematode worm, Platyhelminths worm Helminth worms are a major cause of disease in animas, including Humans Viruses Not truly “microorganisms” because they are not alive
Image of page 3
microscopic, infectious particles Bacteriophage: virus that infects bacteria extremely small (100 nanometers) initially called “filterable agents” structure and terminology Naked Virus a nucleic acid enclosed in a capsid (composed of capsomeres) Ex: bacteriophage, T4, Tobacco mosaic virus (first virus to be discovered) Enveloped Virus Capsid surrounded by a lipid bi-layer from a cell it infects Ex: herpes virus, pox virus (largest of all viruses) Virus Genome Diversity genome can be DNA (can be single or double stranded) or can have RNA (single or double stranded) Viruses require a living cell for replication (intraobligate) Lytic Virus: after reproduction, particles assemble inside the host, then exit to exterior (glycose) Temperate (Lysogenic) Viruses remain in latent state viral genome integrates DNA into host cell genome (called prophage) Host- Cell DNA polymerase copies chromosome cell divides (now called a lysogenic cell) can be induces to produce viral particles (lytic stage) such as temperature or pH stress Other possible outcomes
Image of page 4
Image of page 5

You've reached the end of your free preview.

Want to read all 15 pages?

  • Spring '08
  • Barclay
  • Bacteria, proton motive force, ex

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture