Lecture 14 Protists Flashcards
1
Q
- Prominent members of ecosystems
- Useful as model systems and in industry
- Some are human and plant pathogens
- among the 20 most frequent microbial causes of death world - wide, 6 are eukaryotic
- Two groups : Protists and Fungi
A
Eukaryotic Microorganisms
2
Q
Organelles of Eukaryotic Cells
A
- Endoplasmic Reticulum
- Protein synthesis - ribosomes
- Golgi Apparatus
- Chemical modification, packaging, secretion
- Mitochondria
- Powerhouses of cell - ATP by e transport and oxidative phosphorylation
3
Q
Importance of Protists
A
- Important link in food chains
- Plankton in aquatic habitats
- Radiolarians, Diatoms and Foraminiferans
4
Q
General Features of Protists
A
- Terrestrial or aquatic
- Some parasitic in humans, animal sand plants
- Motile
- Flagella, also cilia and pseudopodia - Reproduction:
- Sexual and/or Asexual
5
Q
Micronucleus
A
-“true nucleus”, normal chromosomes, mitosis
6
Q
Macronucleus
A
- thousands of short, linear chromosomes
- Genes for growth and feeding
7
Q
Trichocysts
A
- Filament projections
- Ejected
- Defense , Food Capture
- Seath the Scaleless
8
Q
Metabolism
A
- can be photosynthetic (oxygenic)
- also chemoorganoheterotrophs and mixotrophs (organic and inorganic)
9
Q
Nutrition
A
- Solid nutrients by phagocytosis
- Soluble nutrients by facilitated diffusion and active transport
10
Q
Encystment
A
- development into dormant stage -cyst
- protection, transmission
11
Q
Excystment
A
-escape from cyst to metabolically active, motile form - trophozoite
12
Q
- Unicellular green algae
- Cell walls of celulose
- Oxygenic photosynthesis
- Motile via two flagella
- Stigma (eyespot)
- Phototaxis
- Photoreceptors - Potential Biofuel Source
A
Chlamydomonas
13
Q
Life Cycle of Dictyostelium A cellular Slime mold
A
- Nutrition = bacteria by phagocytosis
- Free-living amoeboid cells
- Aggregate to form motile slug
- Signal = cAMP
- Fruiting body with spores
- Spores released
14
Q
- Protozoan parasite
- Human pathogen, Giardiasis
- Cysts ingested
- Trophozoites attach to intestine
- Disrupts nutrient and water flow
- Severe diarrhea, fluid loss
- Backpackers, if filtering water, ensure filter removes cyst form
A
Giardia
15
Q
- Free-living, aquatic, amoeba
- Thermophile - warm, high nutrient, fresh water
- Trophozoite enters nose travels to brain and destroys tissue causing brain swelling and death
-Primary amebic meningoencephalitis
A
Naegleria fowleri
