Introduction 1 of 2

Question 1

what are some reasons to work/study microorganisms? (5)

Answer 1

1. grow rapidly
2. easy to work witth
   
   1. genetic engineering
3. inexpensive media
4. does not take up much room
5. cheaper compared to other forms of life

Question 2

what are the three major groups/domains?

1. kingdom
   
   1. domain

Answer 2

1. prokaryotes- lack a well defined nucleus and organells
   
   1. Bacteria(eubacteria)
   2. Archaea (ancient)
2. eukaryotes
   
   1. Eucarya- contain a nucleus(cellular organelles)

Question 3

bacteria

1. cellular morphology
2. cell walls composed of
3. multiply by
4. motility use
5. compare archae

Answer 3

1. cellular morphology
   
   1. rods
   2. cocci
   3. spirillum
2. cells walls composed of peptidoglycan
   
   1. ​not found in other organisms
3. multiply by binary fission
4. motility by use of flagellum
5. archaea
   
   1. same shape, size, reproduction and physical appearance
   2. cell wall is different
   3. grow in extreme enviornments

Question 4

List 3 eukaryotes

Answer 4

1. algae
   
   1. chlorphyll
   2. photosynthesis
   3. multicellular types
2. fungi
   
   1. derive energy from organic carbon sources
   2. many aremulticellular
3. protozoans
   
   1. amoeba, parameciums

Question 5

what is a piece of nucleic acid surrounded by a protein?

Answer 5

virus

1. all living organisms can be infected by a virus
2. must replicate intracellularly

Question 6

what infectious agent appears to be only protein?

Answer 6

prions

1. no nucleic acid
2. responsible for neurodegenerative disease
   
   1. kreutzfeld-jakobs disease
   2. scrapie
      
      1. mad cow
   3. kuru
3. spongiform encephalopathies

Question 7

describe the bacterial DNA structurtes

Answer 7

1. Bacterial chromosome
   
   1. circular, single dsDNA
   2. super coiled
   3. located in nucleoid
      
      1. ​discreet gel like region
2. plasmids
   
   1. smaller, circular pieces of dsDNA
   2. antibiotic resistance, toxin producing
   3. explains incresing frequency of antibiotic resistance
3. ribosomes
   
   1. 70S
      
      1. 30S and 50S
4. membrane
   
   1. electon transport and energy production
   2. lipid bilayer embedded with proteins
      
      1. hydrophobic
      2. makes the inside of the lipid bilayer impermeanble to water
      3. fluid mosaic model- dynamic nature of proteins in the layer
5. cell wall
   
   1. recognied by the immune system
   2. gram negative
      
      1. counter stain- Safranin, NOT
   3. peptidoglycan- gram positive
      
      1. stain purple
      2. alternating series of 2 subunits linked by glycan chains
         
         1. nam
            
            1. ​N-acetylmuramic acid
         2. nag
            
            1. ​N-acetylglucosamine

Question 8

compare and contrast gram negative and gram positive

Answer 8

1. cell wall
   
   1. positive
      
      1. 40-80% of dry weight
      2. 30 layers
      3. teichoic acid
         
         1. stick out above the peptidoglycan layer and are negatively charged
            
            1. gives the cell and negative polarity for the (+) charged crystal violet stain to attach
      4. purple
   2. negative
      
      1. line is resistant to many antimicrobial medications
      2. cell wall is composed of onlly a thin layer of peptidoglycan surrounded by an outer lipid bilayer membrane
      3. generates substructures/areas
         
         1. periplasmic space
            
            1. _​_filled with proteins and _periplasm_ involved in such cellular activites as degradation and transport
      4. outer membrane
         
         1. composed of lipopolysaccharides LPS
            
            1. ​endotoxin
            2. lipidA
               
               1. ​anchor LPS molecule in membrane.
               2. recognized by body
            3. o-specific polysaccharide side chain
               
               1. ​unique combination of sugar molecules
               2. used in identification
      5. porins act as channels

Question 9

what is Gram-Negative distinguishing feature on the cell wall

1. considered a…
2. composed of. 2
3. stimulates
4. causes
5. large amounts lead to

Answer 9

1. enodotoxin
2. composed of
   
   1. lipid A
      
      1. anchor the LPS molecule in the lipid bilayer and is responsible for the body’s ability to recognize the presence of invading basteria
   2. O specific polysaccharide side chain
      
      1. ​unique combination of sugar molecules
      2. used to identify the microbe
3. stimulates immune response
4. cause of fever, shock
5. large amounts released into the blood stream leads to DIC
   
   1. ​Disseminated intravascular coagulation
      
      1. inappropriate activation of the oagulation cascape leading to fibrinolysis

Question 10

discuss two species that are an exception to the gram stain.

Answer 10

1. Mycobacterium
   
   1. HAVEA CELL WALL containing peptidoglycan interwined with waxlike lipid molecules of mycolic acids
   2. gram stain DOES NOT WORK
   3. special staining
2. Mycoplasma
   
   1. lack a peptidoglycan cell wall
   2. incorporate steroids into their membranes

Question 11

layer that functions as a means of protection/attachment

1. names
2. composition- name two
3. develop to

Answer 11

1. glycalyx/slime/capsule
2. composed of polysaccharides such as
   
   1. dextrans
   2. glucans
3. biofilms
   
   1. dental plaques

Question 12

responsible for most types of bacterial motility

1. energy
2. acts like
3. parts-3
4. used for

Answer 12

flagellum

1. energy is expended by flagellum using proton motive force
2. acts like a porpeller
3. parts
   
   1. filament
      
      1. portion that ectends into the outside
   2. hook
      
      1. ​connects the filament to the cell surface
   3. basal body
      
      1. anchors the flagellum to the cell wall and cytoplasmic membrane
4. used for
   
   1. motility
      
      1. property of motion by use of flagella
   2. chemotaxis
      
      1. directed towards chemical attractants and away from chemical repellants
         
         1. survival device
            
            1. avoidin toxins
         2. growth
            
            1. finding food

Question 13

shorter and tthinner than flagella

1 name

2and 3 explain the two types

Answer 13

1. pili
2. fimbriae
   
   1. type of pili that attach cells to specifici surfaces
   2. tips of protein molecules called adhesins
      
      1. these adhere to a specific molecule
      2. example
         
         1. E.coli have adhesins in their pili that are specific for intenstinal surfaces- leading to diarrhea
3. sex pili
   
   1. involved in conjugation
      
      1. horzontal gene transfer of plasmids

Question 14

regions where high molecular weight polymers accumulate when that nutrient is available in excess

list three examples

Answer 14

1. storage granules
2. examples
   
   1. glycogen
   2. poly-beta-hydroxybutyrate
   3. volutin(phosphate)
      
      1. useful in waste water treatment.
      2. these microorganisms scavenge phosphate- an eviornmental pollutant

Question 15

cell structure that is often produced by aquatic bacteria

1.

Answer 15

1. gas vesicles
   
   1. rigid, protein bound compartments whereby gases can flow freely in
   2. give the microorganism buoyancy
      
      1. important to photosynthetic organisms requiring certain light

Question 16

Some cells are very hard to kill. What is the structure/process that contirbutes to the viability of these organisms.

1. explain the two states
2. can survive
3. famous producers - 4

Answer 16

1. endospores
   
   1. dormant cell types that germinate into actively multiply cell formed by sporulation
      
      1. vegitative cell - the cell that is actively multiplying (seperate from sporulation)
   2. can survive
      
      1. heat
      2. dessication(drying)
      3. toxic chemicals
   3. famous endospore producers
      
      1. clostridium botulinum
         
         1. botulism
      2. clostridium perfringens
         
         1. gangrene
      3. clostridium tetani
         
         1. tetanus
      4. bacillus anthracis
         
         1. anthrax

Question 17

what are the 2 major subunits in the peptidoglycan wall?

Answer 17

1. peptidoglycan wall- with two covalently linked together glycan chains
   
   1. NAM
      
      1. N-acytelmuramic acid
   2. NAG
      
      1. N-acytlglucosamine

Question 18

A patient was presented at the hospital and blood analyzed. The blood was found with the coagulation cascade underway in an anticoagulation blood collection specimen. What could be happening to this patient? bacteria type?

Answer 18

Disseminated intravascular coagulation- DIC

1. inappropriate activation of the coagulation cascade and fibrinolysis
2. from gram negative bacteria
   
   1. LPS
      
      1. stimulates the immune system
      2. fever, shock