Exam 1- Microbiology Ch.1, 3, 11, 6, 7 Flashcards
Ch. 1: A Brief History of Microbiology Ch. 3: Cell Structure and Function Ch. 11: Characterizing and Classifying Prokaryotes Ch. 6: Microbial Growth Ch. 7: Prokaryotic Genetics
What is the working definition of microbiology?
study of entities too small to be seen with the unaided human eye
What are the three main questions Scientists searched for in The Golden Age of Microbiology?
- What causes fermentation?
- What causes disease?
- How can we prevent infection and disease?
Who is Louis Pasteur?
“Father of Microbiology”
- responsible for pasturization, fermentaiton, and the Germ Theory of Disease
What may be the most important microbiological event–one that has had a greater impact upon culture and society than that of any disease or epidemic?
Domestication of the yeast used by bakers: Saccharomyces cerevisiae ("sugar fungus that makes beer")
What is the Germ Theory of Disease and who do we have to thank for it?
Discovery: bacteria responsible for spoiling wine + Hypothesis: microbes responsible for diseases
Thank you, Louis Pasteur
What are the components of the Triad or Triangle of Health?
- host (chiro’s focus)
- environment (public health’s focus)
- agent (allopathic medicine focus)
Who is credited with handwashing in preventing infection and disease? How was it discovered?
Ignaz Semmelweis —> noted births vs mortality of mothers giving birth; med students 20x higher than midwives; “cadaver particles” from the hands of the medical students caused puerperal fever
Who is credited with antiseptic technique? How?
Joseph Lister –> surgeon, noted consequences of inf. of wounds; began spraying wounds, incisions, dressings with carbolic acid and decreased deaths of patients by 2/3
Who is credited with infection control/ filed of epidemiology? How?
John Snow –> determined cause of cholera transmission in London; officials reluctant to believe him, but it stopped outbreak of cholera
Who is credited with smallpox vaccine/ field of immunology?
Edward Jenner–> showed vaccination with pus collected from cowpox lesions prevented small pox
What are the Processes of Life (what organism needs to be able to do in order to be considered alive)?
Growth
Reproduction
Responsiveness
Metabolism
What is the single most important distinguishing characteristic between eukaryotic cells and prokaryotic cells?
nucleus
- Eukaryotes have a nucleus
- Prokaryotes DO NOT have a nucleus
What are the difference between Prokaryotes and Eukaryotes:
- nucleus
- DNA
- size
- structure
- examples
- P-No nucleus; E- nucleus
- P-circular; E-linear
- P-smaller; E-larger
- P-simple; E-complex
- P-bacteria and archaea; E-protozoa, fungi, animals, plants, and algae
What are inclusions and what type of cells have them?
bacteria (prokaryotes)–> little area of cell where store nutrients; may include reserve deposits of chemicals; stored when nutrients abundant, and used when nutrients scarce
What are endospores? What organisms can produce them?
unique, produced by SOME bacteria, is a defensive strategy against unfavorable conditions
Genes: Bacillus and Clostridium
Where is the site of protein synthesis in a cell?
ribosomes
What are the size of prokaryotic ribosomes?
70S
What are the size of Eukaryotic ribosomes? What about their mitochondria?
80S
mitochondria have 70S
What is the importance of knowing that eukaryotic mitochondria contain 70S ribosomes?
b/c prokaryotes contain 70S ribosomes, and tha can be a target for antimicrobial drugs (therefore impacting human ribosomes too)
Which cells contain 70S ribosomes?
BOTH prokaryotes and eukaryotes
What are four functions of bacterial cell walls?
- give bacterial cells characteristic features
- protect cell from osmotic forces
- assist some cells in attaching to other cells
- often a target of antimicrobial drugs
What are the four categories of Bacteria based on cell walls? Which one does not have a cell wall?
- Gram (+)
- Gram (-)
- Mycobacteria
- Mycoplasma (only one w/o cell wall)
Which type of bacteria have a thick peptidoglycan layer? What color do they stain after a Gram stain?
Gram (+) bacteria; stain purple
How many lipid bilayers do Gram (-) bacteria have? Size of peptidoglycan layer? What do they stain after Gram staining?
- 2 lipid bilayers
- thin layer of peptidoglycan
- stains magenta
What does a Gram (-) bacteria membrane contain that is of importance and unique to it?
lipopolysaccharide, known as Lipid A
Which type of bacteria has a cell wall and contains waxy, mycolic acid?
Acid-Fast Bacteria, in the genus: Mycobacterium
What does a bacteria with the genus Mycoplasma tell us?
- NO cell wall!!!
- has distinctive “fried egg” appearance
- colonize osmotically protected habitats
What is osmosis?
movement of water through semipermeable membrane, from an area of lower solute conc. to an area of higher solute conc.
What happens to a cell without a cell wall that is placed in an isotonic solution? What if cell has a cell wall?
Both are the same; water moves in and out of cell evenly (due to solutes being equal inside of and outside cell)
What happens to a cell with no cell wall that is placed in a hypertonic solution? What can occur? What if cell has a cell wall?
cell loses water;
crenation can occur –> which is loss of cell function due to loss of TOO much water
~same thing
What happens to a cell with no cell wall that is placed in a hypotonic solution? What if cell has a cell wall?
water will rush into the cell and cell will burst
w/ cell wall–> water will rush inside, but cell will NOT burst
How can we tell by the genus name if a cell if a Gram (+) Bacteria? What are the exceptions?
Genus name ends in -us or -um Exceptions: - Listeria - Nocardia - Actinomyces - Streptomyces
How can we tell by the genus name if a cell is a Gram (-) Bacteria? What are the exceptions?
Ends in - a or -er Exceptions: - Pseudomonas - Haemphilus - Vibrio - Proteus - Bacteroides
How can we tell by the name if it is an Acid-Fast Bacteria?
Genus name is “mycobacterium”
TB, Leprosy
How can we tell by the name if it is a bacteria with no cell wall?
Genus name is “mycoplasma”
pneumonia
What are the 5 typical prokaryote morphologies?
- coccus
- bacillus
- vibrio
- spirochete
- pleomophic
What does morphology mean? What does arrangements mean?
the shape of ONE cell
how cells “hang out” in groups
What do these morphologies mean?
- coccus
- bacillus
- vibrio
- spirochete
- pleomorphic
- round/sphere
- rod shape
- bent rod, comma shape
- corkscrew
- all diff shapes