M5 Eukaryotic Microbes

• Algae

  Photosynthetic, eukaryotic organisms
• Algae produce energy by photosynthesis
• All algal cells consist of cytoplasm, a cell wall, a cell membrane, a nucleus, plastids, ribosomes, mitochondria, and Golgi bodies
• Most algal cell walls contain cellulose
• Algae are classified as green, golden, brown, or red algae
• Prototheca is a very rare cause of human infections
• Phycotoxins

  Algae in several other genera secrete toxic substances. These are poisonous to humans, fish, and other animals.
• If ingested by humans, the phycotoxins produced by the dinoflagellates that cause red tides can lead to a disease called paralytic shellfish poisoning
• Protozoa

  Are nonphotosynthetic, eukaryotic organisms. They are unicellular, free-living and found in soil and water
• Pellicle

  Serves as protection
• Two stages of typical protozoan life cycle:

  Trophozoite and Cyst
• Trophozoite

  The motile, feeding, and diving stage
• Cyst

  The nonmotile, dormant and survival stage
• Parasitic protozoa cause human diseases such as malaria, giardiasis, and trypanosomiasis
• Amebae

  Move by means of pseudopodia (false feet)
• Ciliates

  Move by means if harilike cilia
• Flagellates

  Move by means of whiplike flagella
• Sporozoa have no visible means of locomotion
• Entamoeba histolytica

  Cause of amebic dysentery
• Balantidium coli

  The cause of balantidiasis
• Giardia intestinalis

  The cause of giardiasis
• Plasmodium spp.

  The cause of malaria
• Mycology

  The study of fungi
• Mycologists

  Scientists who study fungi
• Fungi

  Are the garbage disposers of nature
• Chitin

  Fungal cell walls contain a polysaccharide called?
• Hyphae

  Some fungi are unicellular, while other grow as filaments called?
• Mycelium

  Hyphae intertwine to form a mass called?
• Septate hyphae

  The hyphae are divided into cells by cross wall ors septa
• Aseptate hyphae

  The hyphae do not contain septa
• Two general categories of spores:

  • Sexual spores

  • Asexual spores (also called conidia)
• Classification of fungi:

  Mode of sexual reproduction and type of sexual pore they produce
• Six phyla of fungi:

  • Zygomycotina

  • Chytridiomycotina

  • Ascomycotina

  • Basidiomycotina

  • Mycosporidia

  • Deuteromycotina
• Yeasts

  Are eukaryotic, unicellular organisms that lack mycelia
• Blastospores or blastoconidia

  Individual yeast cells can be observed only using a microscope
• Yeasts usually reproduce by budding
• Pseudohypha

  A string of elongated buds
• Chlamydospores

  Some yeasts produce thick-walled, spore-like structures called?
• Yeasts have been used for centuries to make wine and beer
• Candida albicans

  Is the yeasts most frequently isolated from human clinical specimens, and is also the fungus most frequently isolated from human clinical specimens