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define prokaryote and eukaryote?
- Prokaryote- NO nucleus
- Eukaryote- nucleus
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functional anatomy of Prokaryote?
- 1 circular chromosome not enclosed in membrane
- no histones
- no organelles
- peptidoglycan cell walls
- binary fusion division
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what are histones?
what makes DNA coil and wrap up tight
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Functional Anatomy of Eukaryote?
- paried chromosomes enclosed in nuclear membrane
- histones present
- organelles present
- polysaccharide cell walls
- mitotic cell division
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basic shapes to prokaryote?
- Coccus- sphere
- Bacillus- rod
- Spirrila- spiral/cork screw
- wierd shapes: star shaped stella, square shaped haloarcula
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average size of prokaryote?
0.2-1.0 um x 2-8 um
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most bacteria are how many shapes?
monomorphic - meaning 1 shaped
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a few bacteria can have multiple shapes which is defined as?
pleomorphic - multiple shapes
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how are cocci arranged?
- Pairs - diplococci
- clusters- staphylococci
- chains- streptococci
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how are bacilli attached to each other?
end to end, never in middle
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arrangement of bacilli?
- pairs- diplobaccili
- chains- streptobacilli
- there is no staphylo arrangement in rods
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shapes of spiral bacteria?
- vibro- comma shaped, only one bend
- spirilla- rigid, helical shape
- spirochetes- flexible, helical shape
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name the outer structures?
- glycocalyx
- flagella
- axial filament
- fimbriae
- Pili
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characteristics of glycocalyx?
- outside cell wall
- usually sticky
- protects from dehydrations, and limit outward diffusion
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how is glycocalyx organized?
- Organized (capsule)
- prevents phagocytosis
- composed of sugards to allow for attachment to surfaces
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if the outer cell wall of cell is unorganized and loose what is it called?
slime layer
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if outer cell wall of cell is organized what is it called ?
capsule
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during a negative stain what is the difference between capsules adn slime layers?
- capsules are more regular and organized looking
- slime layer are more diffuse and less organized
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function of flagella?
locomotion
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characteristic of flagella?
- consist of chains of flagellin
- attached to a protien hook
- anchored to wall and membrane by basal body
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flagella arrangement?
- single- monotrichous
- on both ends- amphitrichous
- 2 or more on one or both ends- lophotrichous
- all over the cell- peritrichous
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how do flagella move?
chemotaxis- directional movement according to chemical gradient. tumble and run. toward (attractant) or away (repellant)
phototaxis- movement according to light gradient
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describe what tumble and run is?
flagella move in the direction of the attraction. the runs are longer (movement in 1 direction) and the tumble is less (stop and spin).
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what are axial filaments?
- endoflagella - flagella on inside of cell
- located in spirochetes (create the spiral pattern of spiral bacteria)
- anchored at one end of cell
- rotation causes cell to move
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what are fimbriae?
hairlike projections that allows for attachment so microbes can colonize.
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what are pili?
- allow for transfer of genetic material from one cell to another.
- usually longer then fimbriae
- cells usually one have 1 or 2
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describe the cell wall?
- determines the shape
- in some cases, recognized by host immune system
- target for antibiotics
- prevent osmotic lysis
- made of peptidoglycan (prokaryote)
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gram positive cell wall?
- thick petidoglycan,
- teichoic acids,
- in acid fast cells, contain mycolic acid
- help regulare movement of cations
- polysacharides provide antigenic variation
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gram negative cell wall?
- thin peptidoglycan ,
- no teichoic acids
- outer membrane
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describe the extra outer membrane of gram negative cell wall?
- contains lipopolysaccharides
- lipoprotiens-
- phospholipids
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in gram positive cell wall what does techoic acid do?
- lipotechoic acid lins to plasma membrane
- wall techoic acids link to peptidoglycan
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in gram negative cell wall what does lipopolysaccharides do?
barrier to antibiotics and surface molecules/antigens are useful in identification.
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in gram negative, what does a strong negative charge protect from?
phatocytosis
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how gram stain works ?
- stain-crystal violet
- mordant- iodine
- alcohol -if gram positive-dehydrates or disolves peptidoglycan and crystal violet/iodine stuck inside cell
- if gram negative-alcohol dissolves outer membrane and leaves holes in peptidoglycan. the crystal violet and Iodine is washed out.
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what does lysozymes and penicillin do to cell walls?
- lysozyme digests disaccharide in peptidoglycan
- penicillin inhibits peptide-bridges in peptidoglycan (why it is given to gram positive bacteria b/c they have more peptidoglycan )
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characteristics of plasma membrane?
- fluid mosaic model- self healing puncture proof structure
- phospholipid bilayer
- contains peripheral, integral, transmembrane proteins
- selectively permeable
- enzymes for ATP production
- photosynthetic pigments on foldings called chromatophores or thylakoids
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what damages plasma membrane?
- alcohols
- detergents
- polymyxin antibiotics (neosporin)
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types of movement across membrane?
- simple diffusion- movement from high to low concentration
- osmosis- water diffusion
- facilitated diffusion- transporter protiens
- active transport (against gradient)- transporter protiens/ATP
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what is cytoplasm?
stuff inside plasma membrane
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characteristics of cytoplasm?
- nuclear area has nucleoid
- free ribosomes
- inclusions- liquid, gas or other substances in cell
- endospores
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list of inclusions
- gas
- metachromatic granules
- lipid bubbles
- polysaccharide granules
- sulfur granules
- carboxysomes
- magnetosomes
- phosphate reserves
- energy reserves
- protien covered cylinders
- iron oxide reserves
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what are endospores?
- resting cells
- durable, resistant form
- protect agains desiccation, heat and chemical
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define sporulation?
endospore formation
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define germination?
return to active form (vegetation state)
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