The Microbial World Flashcards
organisms and acellular entities too small to be clearly seen by the unaided eye
microorganisms
microorganisms are generally LESS THAN/EQUAL TO ____ ___ in diameter
1 mm
microorganisms are often ____
unicellular
what do all microorganisms LACK?
lack highly differentiated tissues
T/F: all microorganisms are less than/equal to 1 mm in diameter and are unicellular
false
exceptions to microorganism (2)
- not always small (algae can be 12 in. in diameter)
- some things that are super small are actually multicellular animals
how do you tell if an organisms is a microorganism or not?
look at the tissues + determine if they are highly differentiated or not
–> if they are, then its prob an animal
–> if not, its a microorganism
organisms and biological entities studied by microbiologists can be _____ or _____
cellular or acellular
CELLULAR organisms/entities include (4):
1) fungi
2) protists
3) bacteria
4) archaea
fungi examples (2-2):
- yeasts
- molds
- could potentially add mushrooms
protist examples (3):
- algae
- protozoa
- slime molds
bacteria example (1):
E. coli
archaea example (1):
methanogens (release methane gas)
methanogens, an example of archaea, release ____ ____
methane gas
ACCELULAR organisms/entities include (4):
1) viruses
2) viroids
3) satellites
4) prions
what are viruses composed of?
protein + nucleic acid
what are viroids composed of?
RNA
what are satellites composed of?
nucleic acid (often RNA)
what are prions composed of?
protein
which of the ACELLULAR organisms cause PLANT disease?
viroids
which of the ACELLULAR organisms can cause ANIMAL disease (2)?
satellites (and tech. prions)
which of the ACELLULAR organisms cause HUMAN diseases?
prions
“kary” means _____, referring to the nucleus
nut
2 types of microbial cells:
prokaryotic and eukatryotic
type of microbial cells that lack a true-membrane bound nucleus (not absolute)
prokarytic cells
type of microbial cell that have a membrane-enclosed nucleus and other membrane-bound organelles; are more COMPLEX morphologically; usually LARGER than the other type
eukaryotic cells
bacteria and archeons are both _______ cells
prokaryotic
T/F: all bacteria have a cell wall
false
little piece of DNA; most eukaryotic cells do NOT have them
plasmids
T/F: not all eukaryotic cells have a cell wall
true
what structural components do ALL cells share (4)?
- cytomplasm
- cytoplasmic membrane
- ribosomes
- genome made of DNA
DNA is stored as a _____ in prokaryotic cells and within a ______ in eukaryotic cells
nucleoid; nucleus
most eukaryotic cells do not have ______ like prokaryotic cells do
plasmids
properties of ALL cells (4):
- structure
- metabolism
- growth
- evolution
propterty of all cells: all cells use info. encoded in DNA to make RNA and protein; all cells take up nutrients, transform them, conserve energy, and expel wastes
metobolism
2 types of metabolism:
1) catabolism
2) anabolism
type of metabolism: transforming molecules to produce energy and building blocks; BREAK DOWN
catabolism
type of metabolism: synthesizing macromolecules; BUILD UP
anabolism
property of all cells: information from DNA is converted into proteins, which do work; proteins are used to convert nutrients from the environment into new cells
growth
“growth” in microorganims means :
increase in cell #
property of all cells: chance mutations in DNA cause new cells to have new properties, theryby promotoion this; phylogenic trees built from DNA seq. capture these type of relationship between species
evolution
properties of SOME cells (4):
- differentiation
- communication
- motility
- horizontal gene transfer
property of some cells: form new cell structures, such as as a spore
differentiation
property of some cells: cell interact with eachother by chemical messengers; can change gene expression and cause cells to act differently depending on the environment
communication
property of some cells: capable of “self-propulsion”; ex: flagellum
motility
property of some cells: cells can exchange genes by several mechanisms
horizontal gene transfer
GENERAL size of eukaryotic cell =
8 nanometers (similar to RBC)
GENERAL size of prokaryotic cell =
3 nanometers
size RANGE of eukaryotes:
0.8 nanometers - millions of nanometers
size RANGE of bacteria/archaea:
0.2 nanometers - 750 nanometers (visible)
size RANGE of viruses:
0.01 nanometers - 2.3 nanometers
genus of bacteria that lacks a cell wall around the membrane
mycoplasmas
biggest eukaryotic cell
ostrich egg
some viruses can fall in the _____ size range
bacteria
SA to volume ration formula =
3 / r
the smaller an organism, the larger the ______ ______
SA-volume ratio
advantages to being small (3):
- bring in stuff faster
- get rid of waste faster
- reproduce faster which leads to more mutations = ADAPT FASTER (and survive extreme conditions)
since eukaryotics are generally larger, what do thye have to combat being less efficient in bringing materials in?
organelles
which as a larger SA:volume ratio (3/r)?
r=1 or r=2
r=1 (SA:volume ratio is 3, compared to 1.5)
cell morphology components (2):
- shape
- arrangement
most common cell shapes =
cocci and bacilii
sphere shaped cells
cocci
rod shaped cells
bacilli
3 main shapes of cells:
1) spheres (cocci)
2) rods (bacilli_
3) spirals (spirillum and spirochete)
what’s the difference between spiriullum and spirochete cells?
both helices but spirillum are RIGID and spirochetes are FLEXIBLE
types of cocci cell shapes (5):
1) diplocci
2) streptococci
3) staphylococci
4) tetrads
5) sarcinae
type of cocci: pairs
diplocci
type of cocci: chains
streptococci
type of cocci: grape-like clusters
staphylococci
type of cocci: 4 occi in a square
tetrad
type of cocci: cubic configuration of 8 cocci
sarcinae
what type of cocci is staph?
staphylococci (grape-like clusters)
types of bacilli cell shapes (2):
- coccobacilli
- vibrios (kinda)
type of bacilli cell shape: very short rods
coccobacilli
type of bacilli cell shape: resemble rods, comma shaped
vibrios
what cell shape is E. coli?
coccobacilli
other shapes & arrangements of cells (4):
- filamentous (mycellium)
- pelomorphic
- unique shapes (star)
- unique arrangements (palisades)
example of filamentous shape of cell =
mycellium
other shapes and arrangement: network of long, multicellular filaments
mycellium (filamentous)
other shapes and arrangement: variable in shape
pleomorphic
other shapes and arrangement: star
unique shape
example of unique ARRANGEMENT cell =
palisades
other shapes and arrangement: ends are curved so they stick together; “chinese letters, picket fense”
palisades (unique arrangement)
other shape of cell: coffee-bean shape in pairs
Neisseriae
other shape of cell: example of Palisades arrangement
Corynebaceria
other shape of cell: large cocci in irregular clusters
Mirococci + staphylococci
other shape of cell: moldlike filamentous bactera
Streptomycetes
How did microbes evolve (4 steps)
1) mutation of genetic material
2) new genotypes (genetic code)
3) advantageous phenotypes
4) natural selection (ex: antibiotic resistance)
are bacteria and archaea haploid or diploid?
haploid
how do bacteria and achaea increase genetic diversity?
horizontal gene transfer within the same generation
what’s the advantage of bacteria and archaea being HAPLOID?
mutations can’t be masked by another set of genes (since there’s only one copy of every gene) – can lead to advantageous phenotypes
horizontal gene transfer steps (3):
1) elongation
2) transformation
3) transduction
horizontal gene transfer step: closest to sexual reporudction
elongation
horizontal gene transfer step: take up DNA from their environment
transformation
horizontal gene transfer step: occurs via VIRUSES
transduction
order of origin of Earth (8 groups W/ transistions in atmosphere):
1) Bacteria and Archaea
2) Phototrophic Bacteria
————- transition to an oxygenated atmosphere
3) Cyanobacteria (take up oxygen)
4) Eukarya
—————-oxygen increases, prokaryotes pop up
5) Animals
6) Vascular Plants
7) Mammals
8) Humans
was oxygen present when Bacteria, Archaea, and Phototrophic Bacteria came to be?
no
first known bacteria that used oxyogenic photosynthesis
cyanobacteria
LUCA =
last universal common ancestor
Bacteria and Archaea divered around _____ ___
3.8 bya
Eukarya divered from Archaea around _____ ____
2.0 bya
where did Eukarya diverge FROM?
Archaea
3 domain system based on a comparison of the DNA encoding small subunit ribosomal RNA (rRNA)
Universal Phylogenetic Tree
3 domains of the universal phylogenetic tree:
- Bacteria
- Archaea
- Eukarya
which of the 3 domains of the universal phylogenetic tree are PROKARYOTIC?
bacteria and archaea
which of the 3 domains of the universal phylogenetic tree are EUKARYOTIC?
eukarya
5steps of creating a phylogenetic tree (5):
1) isolate DNA from each organism
2) make copies of rRNA gene by PCR
3) sequence DNA
4) analyze sequence
5) generate phylogenetic tree
in a phylogenetic tree, the LONGER the line/branch, the more _______ there was in their DNA sequences
mismatches
evolutionary distance =
2/9
(2 mismatches out of 9)
why are mitochondria and chloroplasts on separate branches within the phylogenic tree for Bacteria?
they have their own DNA
which theory provides a reason for why mitochondria and chloroplasts have their own DNA and states that “a prokaryote cell engulfed another prokaryotic cell which survived and developed a symbiotic relationship with it”
Endosymbiotic Theory
cyanobacteria and algae give us ____% of our oxygen
70%
archaea are more closely related to ______ than _______
eukaryotes than bacteria (despite being prokaryotes like bacteria)
within the 3 domains of the universal phylogenetic tree, most are microbes/microorganisms except _____, _____, and ______
animals, plants, and fungi
which domains of life include(s) microorganisms?
ALL (archaea, bacteria, and eukaryotes) – all can lack highly differentiated tissue
which domains of life include(s) microorganisms?
could argue all as well
microorganisms of Domain Eukarya (not macro; 2)
1) protists
2) fungi
types of protists (4):
- algae
- protozoa
- slime molds
- water molds
type of protist: plant-like
algae
type of protist: animal-like
protozoa
type of protist: can act like protozoa OR algae
slime molds
type of protist: grow on moist soil or vegetation; caused the potato famine in the 1940s
water molds
types of Fungie (~3)
- yeast
- mold
- might argue mushrooms (still lack differentiated tissue)
a collection of STRAINS that share many stable properties and differ significantly from other groups of strains (look at DNA or CG content)
microbial species
since Bacteria and Archaea do not reproduce ______, the term “species” has a different meaning; NOT defined as an interbreeding natural population
sexually
subset of microbial species; consists of the descendants of a single, pure microbial culture
microbial strain
one strain is designated at the “______ strain” = standard strain; permanent
“type strain”
within the type strain name, such as “E. coli 0157:H7”, the letters have to do with the _____
antigen
within the type strain name, such as “E. coli 0157:H7”, the numbers have to do with what?
the order in which it was discovered
T/F: all strains of microbial species cause the same side-effects in the body when infected
false
who came up with Binomial Nomenclature?
Carl Linnaeaus (1707 - 1778)
what does binomial nomenclature consist of?
genus and species
importance of microorganisms (7)
1) oldest form of life
2) most populous and diverse group of organisms
3) major fraction of biomass and KEY reserviour of essection nutrients
4) play a major role in recycling essential elements
5) some carry out phototsynthesis
6) influence ALL other living things
7) excellent tools for study
it is estimated that there are _______________ microbial cells
2 x 10^30 (more than the predicted stars in the universe!!!!!)
T/F: microbes are found virtually everywhere on the planet
true
most microorganisms are found _______
underground
what % of microorganisms are found underground?
92%-94% (up to 10 km deep)
microorganims are the key reservior of ____ ____
essential nutrients
microorganims house a substantial amount of _____ and 4X more ____ and ____ than plants do
carbone
nitrogen + phosphorus
cyanobacteria give us ____% of our oxygen and are thought to be the _____ ones to do this
75%
first
regarding how microorganims inlfluence all other living thigns, most are _____/_____ while some are _____
beneficial/benign
detrimental
T/F: other life fomrs require microorganims for survival
true
why are microorganisms excellent tools for study (2)?
- easy to grow in lab
- rapid growth
however, less than ___% of microbes are able to be cultured
1%
in what ways do microbes impact humans (8):
1) agriculture
2) energy
3) food
4) disease
5) industry
6) environment
7) human microflora
8) cycling of nutrients
microial impact on agriculture: animals that have a chamber where microbes live in the stomach and transform celluse into fatty acids
Ruminent animals
microial impact on energy/industry: process of glucose —> ethanol
fermentation
microial impact on food: some foods rely on ______ depending on the form (ex: milk, cheese, chocolate)
fermentation
microial impact on disease: can cause death
infectious diseases
microial impact on human microflora: bacteria on skin kill pathogens
skin microbiota (“micrcombination resistance??”)
microial impact on human microflora: chemical messangers in the gut send messages to the brain; can affect mood, cravings, and weight
Gut Brain access
microial impact on cycling nutrients: take nitrogen and fix it to ______
ammonia
the discovery of microorganisms didn’t occur until the ______ due to the lack of technology
1800s
first to describe MICROORGANISMS; described the fruiting structures of MOLDS; came up with the term “cell”
Hooke (1635-1703)
first to observe and accurately describe BACTERIA through his drawings
Leeuwenhoek (1632-1723)
what did Leeuwenhoek think bacteria were?
tiny animals
father of the microscope
Jansen (1500s)
“living organisms can develop from nonliving or decomposing matter” (false tho)
spontaneous generation
discredited spontaneous generation for large animals
Francesco Redi (1668)
who disproved spontaneous generation through an experiment that involved flasks and trapping dust and microorganims?
Louis Pasteur (1864)
other accomplishments of Louis Pasteur (5)
- demonstrated that microorganisms carried out fermentations
- discoveries led to the development of microbial control methods (pasteurization and the asceptic technique)
- discovered attenuation
- developed vaccines for anthrax, chicken chloera, and rabies
- solidified the germ theory of disease
Louis Pasteur disproved that fermentation was strictly a _____ process
chemical
developed for wine first; process of heating liquid up high enough to destroy microorganisms and pathogens but not harm the food; not “sterilized”
pasteurization
technique that developed due to Louis Pasteur’s discoveries that prevents contamination
aseptic technique
the “weakening”/reduction in strength of strains of microbes for the development of vaccines; discovered by Louis Pasteur; injected chickens w/ cholera
attenuation
first person to be inoculated against rabies by Louis Pasteur thanks to his vaccine
Joseph Miester
states that microorganisms known as pathogens or “germs” can lead to disease + rotting (bc microbes eat it)
Germ Theory of Disease
indirect evidence fo the Germ Theory of Disease: discovered hand-washing to prevent “childbed fever” (infection after childbirth);
Ignaz Semmelweis (1847)
indirect evidence fo the Germ Theory of Disease: developed a system of surgery designed to prevent microbes from entering wounds; his patients had fewer postoperative infections; “Father of Modern Surgery”
Joseph Lister (1867)
Joseph Lister is the “Father of ______”
surgery
direct evidence of Germ Theory: established the relationship between certain strains of bacteria and the disease they cause
Robert Koch (1843-1910)
which relationships did Robert Koch establish to provide direct evidence of the Germ Theory (3)?
1) Bacillus anthracis and Anthrax
2) Mycobacterium tuberculosis and Tuberculosis (nobel prize 1905)
3) Vibrio cholerae and Cholera
still used today to establish the link between a particular micoorganism and a particular disease
Koch’s Postulates
Koch’s Postulates (theoretical aspects - 4)
- The suspected pathogen must be present in all cases of the disease and absent from healthy animals.
- The suspected pathogen must be grown in pure culture.
- Cells from a pure culture of the suspected pathogen must cause disease in a healthy animal.
- The suspected pathogen must be reisolated and shown to be the same as the original.
Laboratory tools of Koch’s Postulates (4):
1) microscopy + staining
2) laboratory cultures
3) experimental animals
4) laboratory reisolation and culture
Experimental Aspects of Koch’s Postulates (5):
1) observe blood/tissue under the microscope
2) streak agar plate with sample from either a diseased or healthy animal
3) incoulate healthy animal with cells of suspected pathogen
4) remove blood or tissue sample and observe by microscopy
5) laboratory culture (into a pure culture– must be same organism as before)
singe type of organism/bacteria; descednents of the same cell
pure culture
materials + technique needed for obtaining and growing bacteria in pure cultures (4):
- nutrient broth
- nutrient agar
- Petri dish
- streak plating technique to isoloate bacterial colonies
material needed for obtaining/growing bacteria in pure cultures (Koch’s Postulate): used to GROW bacteria
nutrient broth
material needed for obtaining/growing bacteria in pure cultures (Koch’s Postulate): used to SOLIDIFY bacteria; polysaccharide derived from seaweed; stays solid at @ body temp + most bacteria dont eat it
nutrient agar
who developed the Petri dish?
Richard Petri
what did they used to streak bacteria with (2)?
potatoes or jello (bacteria would eat it tho and it liquifies at body temp (37 degrees Celcius)
used a vaccination procedure to protect individuals from small pox; BEFORE Germ Theory of Disease was identified**; innoculated young boy; coined the term “vaccination” bc “vaca” = cow; realized dairy maids were immune to smallpox bc they were exposed to cow pox
Edward Jenenr (1798)
discovered bacterial endospores and classified bacteria based on shape; termed “bacillus”; also found that endospores “germinate” to active forms when conditions are good
Ferdinand Cohn (1828-1998)
what did Ferdinand Cohn think bacteria were?
plants
dormant structures resistant to heat and other harsh conditions
endospores
discovered penicillin (antibiotic); accidental discovery
Alexander Flemming (1929)
pioneered the use of enrichment cultures and selective media; isolated the first pure cultures of many soil and aquatic bacteria; described the first virus (Tobaccoe mosaic); discovered aerobic Nitrogen fixation
Martinus Beijerinck (1951-1931)
whats the purpose of enrichment cultures and selective media?
to mimic the environment that bacteria like to increase the # of bacterial growth
what is an example of an enrichment culture?
blood agar for pathogens
“Father of Microbiology”
Martinus Beijerinck
discovered numerous interesting metabolic processes (such as anaerobic nitrogen fixation); proposed the concept of chemolithotrophy
Sergei Winogradsky (1856)
process in which organisms get energy from the oxidation of inorganic materials
chemolithotrophy
who discovered AEROBIC nitrogen fixation?
Martinus Beiijerinck
who discovered ANAEROBIC nitrogen fixation?
Sergei Winogradsky
contributor in Molecular Microbiology: “transforming principle:” DNA (not proteins) can transform the properties of cells, clarifying the chemical nature of genes
Griffith (1928)
looking for genomes in the environments of samples (ex: on the skin, in water)
metagenomics
contributor in Molecular Microbiology: “DNA is the genetic material”
Avery, Macleod, and McCarty (1944)
contributor in Molecular Microbiology: DNA structure
Watson, Crick, and Franklin (1953)
contributor in Molecular Microbiology: tree of life/DNA sequencing
Woese / Sanger (1977)
DNA (not proteins) can transform the properties of cells, clarifying the chemical nature of genes
transforming principle (Griffith)
contributor in Molecular Microbiology: revolutionized microbiology; invented the process known as polymerase chain reaction (PCR)
Kary Mullis
contributor in Molecular Microbiology: metagenomics
Handelsman (1998)
Griffith found in his famous experiment (regarding the “transforming principle”) that transformation occurred when a dead smooth cell was put with rough cells through the transformation of its _______
DNA (thought it was going to be a protein)
in Griffiths famous experiment, did rough (no capsule) or smooth (capsulated) colonies kill the mice?
smooth colonies (Strain S)
in Griffiths famous experiment, Strain _____ transformed Straigh R (rough) colonies into deadly smooth colonies when mixed together
S
we are in the ____ golden age of microbio
second
all techniques of DNA came from testing ____ first
bacteria
the Basic Emphases of micrbio regard ______ itself
life
the Applied emphases of micro bio ______ ___ ______
solve a problem
