microbiology final

Question Answer
tetrads those cocci that divide in two planes and remain in groups of four
bacterial cell wall may contribute to the ability of some species to cause disease; may be the site of action of some antibiotics; composed of a macromolecular network known as "peptidoglycan"
gram-positive bacterial cell wall many layers of peptidoglycan; contains teichoic acids; has great mechanical strenghth; susceptible to attack by penicillin
the three types of bacteria shapes cocci; bacilli; spiral
spheroplast partially wall-less gram-negative cell
bacterial colony visible group of bacterial growing on a culture medium
spirochetes helical-flexible when in motion (spirochete-singular)
cytoplasm refers to the substance of the cell inside the plasma membrane
when endospores are formed… the survival of the spore-forming bacterium is threatened, the bacterial cell may form the endospore
types of passive processes simple diffusion; facilitated diffusion; osmosis
amphitrichous having a flagellum or flagella at both ends
4 arrangements of flagella monotrichous; amphitrichous; lophotrichous; peritrichous
lophotrichous tufts or bunches of flagella at one end
gram-negative bacterial cell wall one or very few layers of peptidoglycan; no teichoic acids; more susceptible to mechanical breakage; outer membrane: LPS, lipoproteins, and phospholipids..evades phagocytosis…resistance to penicillin…lipid A of the LPS is referred to as endotoxin
important elements needed by the cell for synthesis for cellular material nitrogen, sulfur, phosporus
diplococci cocci that remain in pairs after dividing
example of a fimbriae Neisseria gonorrhoeae: the causative agent of gonorrhea
streptococci those bacteria that remain attached in chainlike patterns after dividing
sarcinae those spherical bacteria that divide in three planes and remain attached in cube-like groups of eight
spirilla helical- rigid when in motion
vibrios comma shaped
peritrichous flagella covering the entire surface
bacterial cell wall function prevents the bacterial cell from rupturing when the water pressure inside the cell is greater than outside the cell; helps maintain shape of cell; serves as a point of anchorage for flagella
germination going from spore state to vegetative state
pure colony one species
facultative aerobe adapted to survival in the presence of oxygen, but prefer the opposite
facultative anaerobe adapted to survival in absense of oxygen but prefer to live with it
phototaxis the stimulus is light
chemotaxis the stimulus includes chemicals
facilitated diffusion uses the aid of a transporter or carrier protein
mesophiles bacteria that prefer moderate temps and develop best at temps between 25-40 degrees C
thermophiles bacteria that thrive best at high temps, between 40-70 degrees C
minimum growth temp temp below which bacterial growth will not take place
axial filaments (endoflagella) unique type of flagella produced by spirochetes
maximum growth temp temp above which bacterial growth will not take place
nuclear area the region we find the genetic material of the bacterial cell
streptobacilli bacilli that divide across their short access and remains in chains
osmosis the net movement of solvent molecules (water) across a selectively permeable membrane from an area with a high concentration of solvent molecules (water) to an area of low concentration of solvent molecules (water)
spore formation not means of replication, it is a protective or defensive mechanism of bacterial cells capable of the production of endospores
coccobacilli rod-shaped bacteria that are oval and look so much like cocci
obligate (stict) anaerobes microbes that can only survive in an environment devoid of oxygen
psychrophiles bacteria that prefer cold, thriving at temps between 0-25 degrees C
cocci spherical
bacilli rod-shaped
3 types of spiral vibrios; spirilla; spirochetes
ribosomes site of protein sythesis for the cell
inclusions (inclusion bodies) function as the reserve deposits for the cell
optimum growth temp temp at which organisms grow best
lysozyme a digestive enzyme that can cause damage to the bacterial cell wall
protoplast wall-less gram-positive cell
mixed colony more than one species
besides water, what is another important requirement for growth carbon- structural backbone of living matter
osmotic pressure pressured required to prevent the net flow of water across a semi-permeable membrane
staphylococci cocci that divide in multipule planes and form grapelike clusters
diplobacilli rod-shaped bacteria that divide across their short axis and remain in pairs after cell division
microaerophile when the low-oxygen, high carbon dioxide conditions resemble those found in the intestinal tract; require little free oxygen
bacterial cell calculation Bf=Bi*2n
monomorphic do not change shape
monotrichous having a single flagellum
pleomorphic bacterial cell that changes shape
how does the gycocalyx enhance the virulence? resisting phagocytosis
flagella bacterial structure that function for movement and provide mobility for the cell
simple diffusion moves substances like oxygen, carbon dioxide, and water
glycocalyx capsule; slime layer
many prokaryotes secrete a sticky gelatinous coating that surrounds the cell wall
capsule the glycocalyx is known as a capsule only when it is organized and firmly attached externally to the cell wall
heterotrophic require complex organic food from a carbon source to grow and develop
passive process substances cross the membrane from an area of low concentration without any expenditure of energy
most bacteria grow best in what narrow pH range near neutrality? ~6.5-7.5
obligate (strict) aerobe microorganisms that can only live in the presence of oxygen
autotrophic self-nourishing bacteria capable of growing in the absense of organic compounds
plasma membrane thin structure lying internal to the cell wall and enclosing the cytoplasm of the cell
semi-permeable or selectively permeable membrane control the movement of substances into and out of the cell: aids in the breakdown of nutrients, aids in the production of energy
group translocation substance being transported is altered chemically during transport across the membrane
important trace elements essential for functions of certain enzymes iron, copper, molybdenum, and zinc
binary fission method of asexual reproduction in bacteria in which cell splits into two parts
active process the cell must use energy to move substances across the membrane from an area of low concentration to an area of high concentration
types of active processes active transport; group tanslocation
active transport the substance is not altered by transport across the membrane
sporulation or sporogenesis the process of spore formation; going from vegetative state to spore state
capriophile microorganisms that grows best at relativity high carbon dioxide concentrations
what is essential for the growth of organisms? water
generation time time required for a cell to divide
endospores form specialized "resting" cells when essential nutrients are depleted

certain gram-positive bacteria, such as those of the genera bacillus and clostriduim

example of an axial filament treponema pallidum- causatie agent of syphillis
fimbriae (pili) bacterial cells that are covered with short hairlike or bristle-like appendages and allow bacteria to attach to surfaces

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