Chapter 1 The Microbial World and You (lecture) Flashcards
What did Robert Hooke contribute to?
-Use of the first microscope(30x)
-Published drawings in Micrographia
What did Robert Hooke view in the microscope?
-viewed the macroscopic life (e.g., insects, molds)
Who was the first to observe single-celled microbes(“animalcules”)?
Antonie van Leeuwenhoek
Define spontaneous generation:
life from non-life; abiogenesis
What do the cellular properties of microbes possess?
-a genome
-metabolize
-respond to change/evolve reproduce
What are cellular microbes?
-Fungi (yeasts, molds)
-Protista(Algae,protozoans)
-Bacteria(E.coli)
-Archea(cyanobacteria)
What are acellular microbes?
-Viruses
-Viroids
-Prions
What are the characteristics of Prokaryotes(bacteria and archaea)?
-Lack of nucleus & organelles
-Single circular Chromosome
-Asexual reproduction
-Cell Wall is common
-Diverse metabolisms(autotrophs & heterotrophs)
What are the characteristics of Eukaryotes (fungi, protists)?
-larger
-posses nucleus
-organelles
-reproduce asexually or sexually
-multiple, linear chromosome
What is archaea classified as?
extremophiles
What are the characteristics of Thermophile microbes?
-grow in hot temperatures (70-110 C)
-hyperthermophiles(>80 C)
-Aerobic/anaerobic
-Sulfur metabolizers
What are the characteristics of Methanogen microbes?
-produce methane
-anaerobic
-found in sewage treatment plants, landfills, ruminant animals
-thermophilic types
What are the characteristics of Halophile microbes?
-require 12-30% NaCl for growth
-Non-chlorophyll based photosynthetic types
-Aerobic
What are viruses?
Rna or Dna contains an acellular particle
Parasitic
Require host cells
Takes over host cell
machinery to replicate
Acellular
Made of 1 type of nucleic acid either DNA or RNA
Not considered living
Who discovered prokaryotes in extreme environments?
Carl Woese
An example of multicellular assemblages?
biofilms
What did the Spallanzani experiment attempt to refute?
Spontaneous generation
What is kingdom Monera broken down to?
-bacteria domain
-Archaea domain
what did the spallanazani expirement consist of?
sealed, sterilized flask failed to grow microbes—-> proponents of abiogenesis lack access to O2 prevented growth
Who refuted spontaneous generation?
Francesco Redi
What did Louis Pasteur study?
studied fermentations of wine/beer; thought to be a strictly abiological process
What did Louis Pasteur discover?
discovered that yeast carry out fermentation;
- in the absence of oxygen(anaerobic),yeast produce(ethanol)
What did Louis Pasteur refute?
-The idea that oxygen is required for growth
-devised the swan neck flask-admitted air but prevented travel of microbe-carrying dust
What did Robert Koch establish scientific principles for?
Linking a specific microbe to a specific disease; established chain of infection
Define pure cultures:
isolation of distinct colonies
each orginating from a single cell
required solid substrate
What did Edward Jenner do?
Used a less virulent form of chicken pox vaccine
Who attenuated vaccines for fowl cholera & rabies?
Pasteur
What is a vaccination?
use a less virulent form of pathogen
How were vaccines attenuated?
heat/chemical treatment
who first used antisepsis?
Semmelewis
who first used disinfection?
Lister
How were microbes produced?
naturally by microbes
What are the fundamental metabolic types?
Heterotrophs & Autotrophs
What is the interconversion of inorganic & organic forms N, S, P, C, and other minerals?
Geochemical cycling by bacteria
what are generally harmless microbes that live stably on and in our bodies?
Normal microbiota or microbe
What is called when a pathogen successfully enters the host, establishes itself, and produces a disease system?
infectious disease
What is biofilms?
when bacteria form specialized surface-attached communities
What are emerging infectious diseases?
unknown disease outbreaks
How does EID arise?
-Mutation
-Acquisition of new genes
-Recombination of genomes
-Cultural & environmental factors
what are some examples of EIDs?
-ebola virus
-SARS
-MERS
-MRSA VRSA
-West Nile virus
-Swine Flu
-Bird Flu
-Zika Virus
Microbe types
which choice below is true?
A. algae: heterotrophic eukaryote
B. bacteria: similar to archaea in that they both lack a nucleus
C. virus: a type of prokaryote cell
D. archaea: generally found in habitats with moderate
environmental conditions
E. protozoan: type of photosynthetic fungus
F. eukarya: has some similarities in common to archaea that
they (eukarya) DO NOT share with bacteria
G. Two of the above is true
G. Two of the above is true
Microbial size ranges.
Eukaryotic microbes: 20-100 um
Prokaryotes microbes: 1-10um
Viruses:0.02 um-0.09 um (20-900 um)
What are generally not considered microbes?
Multicellular “micro-animals” are not microbes
Ex: water bear
Cells comprising tissues are not microbes
Prokaryotes (bacteria & archaea):
Lack of a nucleus and organelles
Single circular chromosome
Asexual reproduction
The cell wall is common
Eukaryotes (fungi, protists):
Larger, posses nucleus organelles
Reproduce asexually or sexually
Multiple linear chromosomes
Thermophiles:
Grow in hot temperatures(70-110 C)
aerobic /anaerobic
hyper thermopiles
Sulfur metabolizers
Methanogens:
Produce methane
Anaerobic
Found in swap(sewage treatment plants,landfills, ruminant animals)
Themophiclic types
Halophiles
Require 12-30% NaCl for growth
Bacteria:
-Green nonsulfur bacteria
-Gram-positive bacteria
-Proteobacteria
-Cyanobacteria
-Spirochetes
-Thermotogales
Archaea:
-crenarchota
-hyperthermophiles
-Sulfur oxidizers
-Halophiles
-Methanogens
-Eukayarchaota
Eukarya:
-microsporidian
-diplomonads
-trichomonads
-Flagellaates
-Ciliates
-Plants
-Fungi
-Animals
-Slime molds
-entamoebas
Acellular:
Viruses composed of protein, nuclic acid
Viroids composed of RNA
Prions composed protein
Fungi
Eukaryotes (organisms whose cells have a distinct nucleus containing the cells’ DNA)
Either unicellular or multicellular
Primarily composed chitlin
Can reproduce sexually or asexually
Obtain nourishment by absorbing organic material from their environment
Protoza:
Are unicellular eukaryotic microbes
Move by pseudopods, flagella or cilia
They use light as a source of energy and carbon dioxide
Can produce sexually or asexually
Algae
Photosynthetic eukaryotes
Sexual and asexual reproduction forms
Cell walls are composed of cellulose
Abundant in freshwater salt water and soil
Produce oxygen and carbohydrates
Play an important role in the balance of nature
Similarities between eukaryotic & prokaryotic:
both contain nucleic acids
Proteins
Kioids
Carbohydrates
Some kinds of chemical reactions metabolize
Slime layer
looser assemblage
what can be virulent factor in pathogens?
Slime layer
what serves to provide motility via rotary motion like a propeller consist of:
flagella protein
what are axial filaments?
are protein fibers attached to both poles of cell and wrap around the cell, underneath an outer sheath
what is pili?
hair like appendages shorter and thinner than flagella
what is fimbraie ?
few to >100 on cell; for attachment to surfaces or cells
-important in biofilm formation
-can be a virulence factor
