Fungi and Characteristics of Prokaryotes
True or False: Protozoa are Prokaryotes while Fungi are Eukaryotes
False, both eukaryotes
Which has a cell wall, Protozoan Parasite or Fungi?
Fungi
Eukaryotes vs Prokaryotes
Pro= "before" Eu= "true" -karyo= nut or kernel -Eukaryotes : have a membrane-bound nucleus -Prokaryotes: --don't have a membrane-bound nucleus --makes up the Domains Archae and Bacteria
Which is more likely to be motile, Protozoan Parasite or Fungi?
Protozoan Parasite
The Archaea
-Archaea are prokaryotes, like bacteria --were grouped w/ bacteria in Kingdom Monera in olden days -have different cell walls from bacteria (no peptidoglycan in Archaea) -many live in extreme conditions --lipids in cell membranes may be branched or have ring-form hydrocarbons, different and adapted to extreme environments ex. thermophiles live in hot springs halophiles live in salty water -not grown in microbiology labs -don't cause disease -some live in gut
What about Archaea-the other Prokaryote?
-Archaea are taxonomically distinct from Bacteria; as different from Bacteria as they are from eukaryotes -live in extreme conditions-high salt, hot springs, etc --BUT some archaea are part of the microbiome, though none of caused disease -have cell walls, but the makeup of them are different than bacteria
Microbe of the Day
-Giardia sp. is a flagellated protozoan parasite with two identical nuclei -two forms --trophozoites: divide by binary fission --cysts: survive in soil and are covered in a shell of chitin -asymptomatically inhabits the gastrointestinal tract of healthy people -in soil, water, or food that has been contaminated w/ poop -causes most common water-borne disease in the US in susceptible hosts -causes severe gastrointestinal pain 7-14 days after ingesting, lasting 1-4 weeks -diagnosed by examining stool samples microscopically or immunoassays -must filter water in areas where it is common
Methanogens (Archaea that produce Methane Gas)
-Obligate anaerobes (only live in places where there is no oxygen) -in environment: produce methane from organic wastes in ponds, lakes, oceans-"swamp gas" -live in colons of mammals --one cow can make 400 liters of methane every day! -Environmental concerns: methane is a potent greenhouse gas, 25x more potent than CO2 --eating beefs is environmentally unfriendly --scientists try to reduce methane output by vaccinating cows against methanogens
How are Prokaryotes different from Eukaryotic Cells? What features do they share?
-bacteria don't have a nucleus -bacteria usually have cell walls --animal cells and protozoa don't have cell walls --Fungi DO have cell walls -bacteria are usually smaller than eukaryotes
The Cytoplasm of Bacterial Cells
-cytoplasm is made up of gelatinous fluid, cytoskeleton, inclusions, ribosomes inside cell -cytosol is liquid portion of cytoplasm --contains dissolved substances and materials
Bacterial Cell Walls
-fxn of cell wall: maintains shape, rigidity -protects cell from osmotic lysis -contributes to pathogenicity (property of causing disease) especially since interacts with immune system -synthesis of cell wall components is used for different antibiotics
The small size of Bacteria gives them a high surface:volume (S:V) ratio
-high S:V ration means that when nutrients are absorbed into cell, they easily diffuse -why is this rapid diffusion beneficial? What "power" does this give to bacterial cells?
Bacterial Plasma (Cell) Membranes
-similar to eukaryotic membranes --fluid mosaic model -made up of a lipid bilayer --amphipathic lipids/ phospholipids -hydrophilic heads pointed outward, hydrophobic tails are inward -integral proteins form pores that control flow of molecules in/out of cell -selectively permeable: controls movement of molecules in and out of cell --mediated by transport proteins (facilitated diffusion, active transport) -location of metabolic processes like respiration, photosynthesis, and lipid synthesis
If bacteria are single cells, what do bacteria look like? How do we describe them? (look at slides)
-streptococcus -staphylococcus -streptobacillus
True or False: Protozoan cysts and Fungal spores are both produced as a mode of reproduction.
False b/c cysts are produced for survival. However, fungal spores are produced for reproduction
True or False: Protozoa and Fungi BOTH have which of the following structures /characteristics?
Motility, no cell walls, yes nucleus, yes multicellularity, no spores, no
Relative Sizes of Microbes
orange-eukaryotic cell tomato- red blood cell red vine- parasite (African Trypanosome) Skittle/M&M: Yeast/Fungus or Large bacteria tic-tac/Mini M&M/Peppercorn- small bacteria (Streptococcus, E. coli) Sprinkles/Chia seeds: large virus (smallpox) grains of sugar: small virus (poliovirus)
Some less common bacterial shapes (look at slides)
star-shaped bacteria square bacteria rosette
What determines bacteria's arrangement?
the plane of division and whether or not the cells separate after they divide
What feature do Protozoa and Fungi have that Bacteria do not?
they have a nuclei while bacteria don't