Exam 1: Pt. 2 Ch.12, 13, 25 Flashcards
Ch.12: Characterizing and Classifying Eukaryotes Ch.13: Characterizing and Classifying Viruses and Prions Ch.25: Applied and Env. Microbiology
What are the three eukaryotic microbes of clinical interest for us?
- Fungi
- Protozoa
- Helminths
(F and P = microscopic)
(P and H = “parasites”)
What microorganims are in the group of fungi?
yeast and mold
What do we call fungus that causes disease?
mycoses
(mycosis = singular)
30% cause disease of plants, animals, and humans
What type of eukaryotic microbes can spoil fruit, pickles, jams, and jellies?
fungi (b/c they love sugar, esp. yeast)
What is the non-reproductive part/body of the fungus called?
Thallus
What are the two types of Thallus of fungus?
(the non-reproductive body)
Hyphae–> long filaments = mold
Buds–> spherical = yeasts
What type of thallus do molds have?
Hyphae
- long filaments
What type of thallus do yeasts have?
spherical Buds
What do we call fungi that produce two types of thalli?
Dimorphic
Generally, what part of the dimorphic fungus causes disease?
the yeast form;
- breast in hyphae (long filaments) and then turn into yeast-like form
T/F. All fungi have some means of asexual reproduction.
True
What are two types of asexual reproduction of fungi?
- Budding
2. Spore Formation
Describe the Budding fungi reproduction form.
- similar to prokaryotic budding
- makes pseudohypha
What are Pseudohypha?
what the budding form of fungal reproduction makes
= a series of buds that remain attached to one another and to parent cell
Can fungi reproduce sexually?
yes, most also reproduce sexually (recall, all can reproduce asexually)
T/F. Protozoa are very pathogenic.
False, very few protozoa are pathogens
Do protozoa have a cell wall?
typically lack a cell wall–>therefore can burst if not in certain env.
What type of environments do protozoa require? What are they like morphologically? How do they reproduce?
- require moist env.
- great morphological diversity (pleiomorphic)
- most reproduce asexually ONLY
What type of form to all protozoa have that is the motile feeding stage?
trophozoite
What type of form do SOME protozoa have that is their hardy resting stage/ encapsulated protozoa?
cyst (similar to endospores of bacteria)
- more successful at being pathogens
What do some protozoa have that actively pump water from the cells? Why important?
contractile vacuoles
- protect them from osmotic lysis
How do viruses pick their host? (very general)
- may be specific–only infect particular kind of cell in particular host (Ex: HIV)
- may be generalists– infect many kinds of cells in diff hosts (Ex: West Nile Virus)
What are the three kinds of viral capsid shapes?
- complex
- helical
- polyhedral
What type of viral capsid shape is…
- spiral
- many shapes
- geodesic dome
- helical
- complex
- polyhedral
What is the MC viral capsid shape?
icosahedron (20 sides) polyhedral
What is Lysogeny?
modified replication cycle of viruses
- infected host cells grow and reproduce normally for generations before they lyse
What is it called when phages carry genes that alter phenotype of a bacterium, changing them from harmless to harmful?
lysogenic conversion
What is the lysogenic replication cycle in bacteriophages?
added steps that cause replication of chromosome and virus and cell division of the bacteria–> until the virus decides it wants to kill the bacteria and release the replicated viruses
What is it called when animal viruses remain dormant in host cells?
latent viruses or proviruses
- could be years with no viral activity
Latent viruses can have a temporary or permanent change, what do those terms mean?
- Temporary = some latent viruses do not become incorporated into host chromosome
- Permanent = incorporation of provirus into host DNA
What are proteinaceous infectious agents that lack nucleic acid?
prions