micro test 2

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the LPS layer in gram-negative cell walls releases ________ that cause _____________ a. enzymes, pain b. endotoxins, fever c. techoic acid, inflammation d. phosphates, lysis

b. endotoxins, fever

if you gram stain a culture and see purple circles arranged in chians, you would call them :

gram-positive streptococci

gram positive cell walls __________.

have a thick layer of peptidoglycan

in what way are the spirochete flagella unusual? how do spirochetes move?

have periplasmic flagella. they move by twisting and flexing

storage structure

inclusions

small circular piece of DNA that carries non-essential genes

plasmid

if a bacterial cell lost its ribosomes, it would no linger be able to _______.

produce proteins

organisms that lack membrane-bound organelles and a nuclear membrane

prokaryotes

all organisms are made up of cells. what are the two fundamental types of cells?

prokaryotic and eukaryotic cells

to which taxonomic group do cyanobacteria belong?

domain bacteria

what is an endospore?

dormant form of bacteria that is resistant to most forms of environmental stress.

Which stain is used to distinguish differences between the cell walls of medically important bacteria?

gram stain

which bacteria are generally harder to kill- gram negative or gram positive?

gram-negative

Reproduction

1. binary fission 2. sexual or asexual processes

list the three most commonly seen bacterial cell shapes.

1. coccus (round) 2. bacillus (rod) 3. spirillum (spiral)

metabolism

1. enzymes 2. synthesis reactions 3. ribosomes

what are the seven basic characteristics that living things share?

1. growth and development 2. reproduction and heredity 3. metabolism 4. movement 5. cell support 6. protection and storage 7. transport systems In and out of a cell

An example of a glycocalyx is a. capsule b. pili c. outer membrane d. cell wall

a. capsule

give two reasons why microbiologists are concerned with classifying bacterial groups?

a. classification makes identification easier b. classification enables scientists to study relationships between bacterial groups

a capsule is used by bacterial cells for all of the following except: a. conjugation b. protection against phagocytes c. adhering to surfaces d. formation of biofilms

a. conjugation

which of the following bacteria are photosynthetic? a. cyanobacteria b. chlamydia c. pseudomonas d. treponema

a. cyanobacteria

the major locomotor in bacteria are a. flagella b. pili c. fimbriae d. cilia

a. flagella

appendages serve two generalized functions for bacteria. what are they? a. b.

a. motility b attachment

list and describe four separate functions of bacterial cell membranes a. b. c. d.

a. selectively permeable barrier and transport functions b. metabolism (electron transport chain) c. photosynthesis (pigments) d. synthesis of cell walls components

what is an acid-fast stain used for and which species of bacteria are acid-fast?

acid-fast stains identify bacteria with a thick waxy coat , such as mycobacteria and nocardia

filaments that are found in the cytosol and maintain cell shape

actin

what is the difference between pili and fimbriae? both are used for __________. pili are used for _____________

adhesion; conjugation

domain of prokaryotes that has many extremophiles

archaea

which prokaryotic domain is most closely related to eukaryotes?

archaea

how do chemical attractants affect the tumble/run cycle of a motile bacterial cell?

attractants inhibit the tumble cycle

which of the following prokaryotes lacks cell walls? a. rickettsias b. mycoplasmas c. Mycobacterium d. archaea

b. mycoplasmas

which of the following is present in both gram-positive and gram-negative cell walls? a. outer membrane b. peptidoglycan c. teichoic acid d. lipopolysaccharides

b. peptidoglycan

which of the following structures is not found in the cell envelope of a bacterial cell? a. cell wall b. ribosomes c. capsule d. glycocalyx

b. ribosomes

name two bacteria that form endospores

bacillus species and Clostridium species

how are the actions of lysozyme and penicillin similar?

both lysozyme and penicillin cause disruption of the cell wall by targeting peptidoglycan

bacterial plasmids will likely carry all the following EXCEPT: a. the gene to use a different sugar source b. antibiotic resistance genes c. genes for proteins required in metabolism d. all of these are commonly seen on plasmids

c. genes for proteins required in metabolism

pili are appendages in _______ bacteria that serve as a means of ______ a. gram positive; genetic change b. gram positive; attachment c. gram negative; genetic change d. gram negative; protection

c. gram negative; genetic change

which of the following is a primary bacterial cell wall function? a. transport b. motility c. support d. adhesion

c. support

which of the following statements is FALSE, concerning bacterial cell walls? a. they have peptidoglycan b. they give cells their shape c. they protect the cell from hypertonic lysis d. they are the target of penicillin action

c. they protect the cell from hypertonic lysis

which structure is not a component of all cells? a. cell wall b. cell membrane c. genetic material d. ribosomes

cell wall

cell support and protection

cell walls

there are two structures made of DNA in the bacterial cell. which is larger and contains essential genes?

chromosomes

there are two structures made of DNA in the bacterial cell. what are they?

chromosomes and plasmids

heredity

chromosomes or plasmids

movement

cilia or flagella

viruses are not considered living things because a. they are not cells b. they cannot reproduce by themselves c. they lack metabolism d. all of these are correct

d. all of these are correct

which of the following is not found in all bacterial cells? a. cell membrane b. a nucleoid c. ribosomes d. cytoskeleton

d. cytoskeleton

which group of bacteria have periplasmic flagella? a. bacilli b. cocci c. vibrio d. spirochetes

d. spirochetes

form of bacteria that is resistant to environmental stress

endospore

phylogenetic classification schemes group bacteria based on _____________

evolutionary relationships

archaeabacteria include:

extremophiles

endospores are used by some bacterial species to reproduce. true/ false

false

smooth, encapsulated bacteria are generally less pathogenic than are rough bacterial strains. true/flase

false

Which phylum contains bacteria with a gram-positive cell wall?

firmicutes

appendages used for motility

flagella

external structure - either slime layer capsule

glycocalyx

which bacterial structure is most directly involved in the formation of biofilms?

glycocalyx

sum of all the chemical reactions in a cell

metabolism

a flagellum is used by a bacterial cell for:

motility

group of bacteria that lack a cell wall and have sterols in their plasma membrane

mycoplasma

why do mycoplasmal cell membranes contain high levels of sterol molecules?

mycoplasmas lack a cell wall and use sterols to strengthen their cell membranes

are endospores used for reproduction?

no

there are two structures made of DNA in the bacterial cell. which genes are commonly found on plasmids?

non essential

what is peptidoglycan and where is it found in bacterial cells?

peptidoglycan is a polymer of long chains of sugar molecules joined by short peptide chains. it provides support and protection from lysis due to osmotic pressure.

polymer of sugars linked together with short peptide chains

peptidogylcan

phenetic classification schemes group based on__________

phenotype or metabolic characteristics

appendages required for conjugation

pili

color of stained gram-positive cells

purple

what gene sequences are commonly used to compare and classify newly described bacteria?

rRNA

Bacteria are taxonomically classified by __________.

rRNA Absequence similarity

what is the function of ribosomes?

required for protein synthesis

a flagellated bacterial cell moving toward a food source will ________:

run more than tumble

transport

semipermeable membranes

periplasmic flagella are found in _________

spirochetes

what is a strain of bacteria?

sub-pieces of a particular type of bacteria.

bacterial endospores function in _________

survival

the major difference between a spirochete and spirillum is ____________

the nature of motility


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