Exam 1 Flashcards
very small organisms that many are too small to see without a microscope
Microorgansims or Microbes
scientific study of microscopic organisms + viruses
Microbiology
Robert Hooke
a built microscope that magnifies 25x
called what he saw “cells”
looked at plants and cork
Antonie van Leeuwenhoek
first to view microbes
a built microscope that magnifies 200-300x
withheld information for his entire lifetime
Louis Pasteur
invented pasteurization to kill off microorganisms
Declared that spontaneous generation is false
invented vaccines to treat diseases; rabies
Robert Koch
Discovered was bacteria causes what diseases. discovered anthrax, cholera, TB
microbes that live in and on your body (3 lbs)
Normal flora (aka microbiota, microbiome)
____ x more flora than human cells
10
Normal flora are usually not…
Pathogenic
What are the 6 major groups of microorganisms?
-viruses
-fungi
-bacteria
-protozoa
-helminths
used to add color to microbes for better observation
stains and dyes
an environment that provides nutrients like water, salts, glucose, nitrogen, and amino acids
A growth media
How many different species of normal flora is there?
500-1000
classification, description, identification, and naming of living organisms.
Taxonomy
What percentage of oxygen do microbes produce?
50%
What doe plants need in soil to obtain nitrogen?
Microbes
Francesco Redi
conducted an experiment that falsifies spontaneous generation with meat and maggots
Life arising from non-living matter
Spontaneous Generation
Describe Pasteurs SG experiment
Used swan-necked flask to boil broth and let sit for 18 mths > no microbes
After tilting the flask > microbes began to appear
Conclusion: life comes from life
Spontaneous Generation is false
the science of where + when disease occurs
Epidemiology
Ignaz Semmelwies
Came up with handwashing after recording data from lying in hospitals in Vienna.
2 sides of hospital had different death rates due to autopsies
Fevers/deaths reduce by 2/3
John Snow
Discovered the source of an outbreak of diarrhea in a certain hospital to be a water source in town using a map and pins
Prevention of infectious disease
Developed in the 14th century
Vaccination
Edward Jenner
Discovered that he can immunize people from smallpox by injecting them with the cowpox virus
Published pamphlet on how to vaccinate
Who created Antisepsis?
Joseph Lister (Amputative Surgeon)
What did Lister do?
1/2 pts die due to infection. Read Semmelweises paper and Pasteurs germ theory paper. Started Antisepsis process by using PHENOL
Robert Kochs Postulates
Same microbe has to be found in every case
1. isolate microbe in culture
2. onnoculte healthy host with pure culture, cause disease
3. re-isolate microbe and see if its identical to original
What did Kochs lab invent?
solid/ food media
stains for viewing microbes + photographing them
aseptic techniques
Created magic bullet that would kill microbes and not tissue
SALVARSON, compound 606
First to view syphilis
Paul Ehrlich
Questions if microbes cause disease by examining yeast and bacteria in wine. Solution was to heat grape juice, then add yeast.
5 years and published paper stating that microbes cause disease
Germ Theory of Disease
Pasteur
Set standard for hygiene in nursing care, proved with statistics that it works
Florence Nightingale
3 reasons why slides are heat fixed?
> Dries the slide
Kills bacteria
Attaches bacteria to slide (or use FORMALIN)
What is the overall charge of bacteria?
-
What is the charge of dyes to stain bacteria?
+
What can you determine abt becateria using a SIMPLE STAIN?
1 (+) stain
size, shape, arrangement
What can you determine abt becateria using a DIFFERENTIAL STAIN?
2 (+) stains, size, shape, arrangement, cell envelope, produce endospores or have a waxy cell wall
Steps to GRAM STAIN
- Add CRYSTAL VIOLET rinse with DIH2O, bacteria is purple
- Add IODINE (1 min), rinse, makes CV 1 molecule
- Add DECOLORIZER (acetone-alcohol) (2-5 sec), rinse
>Gram + CV is trapped in thick cell wall,
>Gram - are colorless bc cell wall is too thin - Puddle + SAFRONIN, rinse
>Gram + stays purple
>Gram - turns pink
Stains used in GRAM STAIN
Crystal Violet and Safronin
Who created the gram stain and what did he study in Berlin?
Hans Christian Gram
What was causing Pnemonia
What do you use ACID FAST stain for?
Mycobacterium (TB, leprosy)
Nocardia (skin+lung infections)
To see if cell was contains MYCOLIC ACID
Steps in ACID FAST stain:
- Begin on slide warm. Add paper, puddle (+) CARBOL FUSCHIN (2 min)
>Turns pink
2.Take off the paper and rinse with DIH2O - Decolorize with acid-alcohol (2-5 sec)
>ACID FAST bacteria have MYCOLIC ACID–stays PINK
4.Puddle (+) METHYLENE BLUE on smear (1 min)
>NON-acid fast stain turns the rest BLUE
Three differential stains
Gram stain
Acid fast
Endospore stain
What is ENDOSPORE STAIN used for?
Bacillus + Clostridium and produces spores
handy, dormant, resistant structure
Endospores
ENDOSPORE STAIN procedure:
- Begin on slide warmer with paper and MALACHITE GREEN (5min)
- Move slide from heat (5 min)
- Remove paper, rinse with DIH2O
100,000 x total magnification
Scans electrons SURFACES
SEM: scanning electron microscope
20,000,000 x total magnification
slices to views organelles, views viruses
TEM+ transmission electron microscope
What are the 2 major morphologies of bacteria?
Cocci and Bacillia
2+ round bacteria produce separately in this
Single Cocci Arrangment
2 round bacteria remain attached
Diplococci Arrangment
Long chains of round bacteria remain attached in 1 plane
Streptococci
BF is 2 planes, 4 round bacteria remain attached
Tetrads Cocci Arrangment
BF is 3 planes, 8 round bacteria remain attached
Sarcinae Cocci Arrangment
BF in random planes, clusters of bacteria remain attached
Staphylococci Arrangment
BF in 1 plane, 2 rod bacteria produce separate
Single Bacilli Arrangment
BF in 1 plane, long chains of bacteria remain attached
Streptobacilli Arrangment
BF 1 plane, 2 bacteria remain attached in a V shape
Palisade/V-shape Bacilli Arrangment
Science of classifying living organims
Taxonomy
Process of putting things into groups based on similarities
Classification
How to write binomial nomenclature:
Genus species (must be italicized)
R. Whittaker’s Taxonomic scheme is based on:
Linnean Taxonomy
Linnaean Taxonomy:
Kingdom
Phylum
Class
Order
Genus
Family
Species
R. Whittakers taxonomic scheme:
5 KINGDOMS:
Animalia
Plantae
Fungi
Protozoa
Prokaryotae (Monera)
What is C. Woese taxonomic scheme?
3 Domains: based on sequencing of Ribosomal DNA
-Archae
-Bacteria
-Eukaryota
What kindgdom and domain are prokaryotes?
K: Monera D: Archae and Bacteria
Hairlike structure that functions in motility
Arrangement:
Polar: 1 flagellum
Peritichous: all-over bacteria
Run + Tumble movement
Flagella
Sticky proteinaceous extensions on bacteria
Shorter than flagella, many the bacterium
Functions: attaches to surfaces, formation in biofilm (plaque)
Fimbria
Long protein extensions
Longer than Fimbria, shorter than flagella
1-10 on bacterium
Functions: sex, sends DNA through it
used as grappling hooks
Pili
May include: outer membrane, cell wall, cell membrane
Cell envelope
Functions in structure and shape
Made up of PEPTIDOGLYCANS (300 layers) + NAM + NAG sugars + AA
Also anchors wall to underlying cell member. by TEICHOIC ACID
Cell wall
4 Cell basics:
- Have DNA
- Cytoplasm/sol
- Ribosomes: site of protein synthesis
- Cell membrane
Basic unit of life
Cell
Proteinatious sticky substance made of polypeptides and polysaccharides
Has:
“capsule” and
“slime layer”
Glycocalyx
What does the glycocalyx protect the bacteria from?
Drying, chemicals, environmentals stressors, loss of nutrients
Also decreases phagocytosis
What else does glycocalyx have to offer?
Can be eaten when there isn’t enough nutrients
Clings and attaches itself to surfaces
Hair-like structure
Functions: motility
Flagella (plural)
Flagellum (singular)
Arrangments of flagella
Polar: 1
Peritrichous: all over bacteria
Run + tumble
Run: counterclockwise
Tumble: clockwise
Sticky bristle-like proteinaceous extensions from bacteria
Shorter than flagella and have many
Fimbria
What is the function of fimbria?
Attaches itself to surfaces and forms BIOFILM
Long protein extensions that aid in attachment to surfaces like grappling
Sex between bacteria (DNA through Pilus)
Pili (plural)
Pilus (singular)
What is the function of cell walls?
structure
shape
protects frmo osmotic forces
What is the cell wall made of gram + bacteria and what does it look like?
Peptidoglycan (protein/amino acid + sugar)
(300 layer)
Alternating molecules of NAG and NAM that are weaved into 4 amino acids
What anchors the cell wall to the cell membrane in Gram POSITIVE bacteria?
Also adds to ion permeability
Teichoic acids
What is the cell envelope of Gram NEGATIVE bacteria made of?
Outer membrane (protects cell wall)
Cell wall
Cell membrane
What is the outer membrane (g negative) made of ?
Lipopolyshaccharides (LPS)
Phospholipids
Proteins
Whats the difference of gram NEGATIVES cell wall?
Its only 2-3 layers
storage for excess nurtients for when needed
Inclusions
Hardy, dormant, resistant.
Surrounded by peptidoglycan
Forms when bacteria are under stress and won’t survive (antibio., no nutrients)
Only 2 genera of bracteria produce them.
Endospores
Bacteria that turns into endospores
Bacillus
Clostridium
What is it called when bacteria form endospores?
Then go back?
Sporulation (6-8 hrs)
Germination (1.5 hrs)
How are endospores made?
Copy DNA surrounded by a double membrane surrounded by a peptidoglycan
Different energy sources:
Light: photo
Organic: hetero
Inorganic: litho
CO2: autotroph
Photoautotroph
ES: light
CS: CO2`
Photoheterotroph
ES: light
CS: organic compounds
Lithoautotroph
ES: Inorganic molecules
CS: CO2
Heterotroph
ES: organic compounds
CS: organic compounds
What are the chemical requirement for microbrial growth?
Carbon
Hydrogen
Nitrogen
Oxygen
50% of dry weight of microbes, needed to build lipids, proteins, nucleic acis
Carbon
12-15% of dry weight of microbes, main source is from earths atmosphere (79% atm.)
Builds proteins, ATP, nucleic acids
Nitrogen
usually get from water
Hydrogen
Air is 20%, 0.3% CO2
Need it to build carbohydrates, lipids, fats, nucleic acids
Oxygen
Required to have oxygen
Use aerobic energy production for ATP (38 ATP, ETC: O)
If no oxygen, fermentation but not long term
Obligate aerobe
No oxygen required, (O kills them)
Anaerobic energy production> 38 ATP (ETC: NO-3 + SO-4)
Obligate anaerobe
Prefers oxygen at 1-10% (atm. 20%)
Aerobic energy production, fermentation
Microaerophile
Uses anaerobic energy production, ferments.
Ignores oxygen
Aerotolerant anaerobes
Aerobic + anaerobic production + ferments
Can survive anywhere, produces ATP everywhere
Facultative Anaerobe
Requires and loves higher CO2 (3-10% CO2)
Capriophile
Cold loving
Below 15 degress celcius
(Not human pathogens, food spoilage)
Psychrophile
Thrive in moderate temp.
20-40 degress celsius
(Human pathogens, human body temp is 37 C)
Mesophile
Heat loving microbe at about 45-80 degress celsius
(compost pile)
Thermophile
Extreme heat loving microbe at over 80 degrees celsius
(live in geysers)
Hyperthermophile
Iron, copper, and zinc act as _________
cofactors for enzymes
Phosphorus is used for ____________
membranes = phospholipid bilayer
What is sulfur used for?
Productions of proteins
grows best in PH 6.5-7.5
Neutrophile
Grows in acidic conditions less than 6.5 PH
Acidophile
Grows in alkaline conditions PH greater than7.5-11.5
Alkalinophiles
Synthetic media, exact comp. is known, expensive and not common
Defined media
Composition varies from batch to batch, Contains extracts (meat, yeast, protein) we use Trypticase Soy Media > soy extract
Complex media
Encourages growth of wanted microbes while inhibiting the growth of unwanted microbes. Generally mannital salt agar > high salt concentration
***Staphylococcus on skin
Selective media
Makes it easier to distinguish different types of bacteria > blood agar > what does bacteria do to cells? (Burst, bruise, ignore)
Some media is selective and ________
Differential media
Short term microbe preservation
Refrigerate
Long term microbe preservation
Deep freeze, 50-90 C for years
Super long term microbe preservation
LYOPHILIZATION: turn into a powder
time required for bacteria to divide by binary fission
Generation time
Stages of bacteria growth
LAG
LOG (most susceptible to damage)
STATIONARY
DEATH
Iron, copper, zinc can act as
Cofactors for enzymes
Organic molecules can act as
Coenzymes
Why do we not rinse capsule stains under water?
Bacterial capsules are soluble in water