Chapter 1 (Introduction to Microbiology) Flashcards
Part 1
Who 1st described bacteria in 1677 with the use of a simple microscope utilizing crude lenses?
Anton Van Leeuwenhoek
The 3 major forms of bacteria that Anton Van Leeuwenhoek described
rod
sphere
spiral
Anton van Leeuwenhoek is considered as:
The Father of Bacteriology
Who developed the compound microscope in 1676 and confirmed Leeuwenhoek’s discoveries?
Robert Hooke
What theory states that life could develop spontaneously from decomposing, nonliving material?
Spontaneous generation (Abiogenesis Theory)
This scientist demonstrated the appearance of maggots in decomposing heat depended on the deposition of eggs by flies that refused the Abiogenesis Theory in the 17th century
Francisco Redi
They disproved the theory of spontaneous generation and proved that life must arise from preexisting life (biogenesis theory)
Pasteur and Tyndall
Who first proposed the Theory of Biogenesis?
Rudolf Virchow (1858)
He was able to filter microorganisms from the air and concluded that this was the source of contamination
Louis Pasteur
Pasteur demonstrated the fermentation of fruits and grains by certain groups of microorganism called what
ferments
Louis Pasteur developed what kinds of vaccines
Chicken cholera vaccines
anthrax vaccine
rabies vaccine
He proved that dust carried germs
John Tyndall
Tyndall found out that bacterial spores could be killed by successive healing in a process called
Tyndallization
He postulated during the 13th century that diseases were caused by invisible living creatures which are called “germs”
Roger Bacon
Who developed the Germ Theory of Disease?
Louis Pasteur
This theory states that each specific infectious disease is caused by a specific microorganism
Germ Theory of Disease
He introduced aseptic surgery by demonstrating the value of spraying operating rooms with aqueous phenol
Joseph Lister
He also developed the first pure culture technique using liquid medium which was the key to identification of bacteria
Joseph Lister
He perfected the techniques of identification of organisms that are in use today, including used of solid media
Robert Koch
In 1876, Koch established the etiologic role of bacteria for ____ by isolating it in pure culture and transmitted the disease to mice
Anthrax
What did Koch discover in 1882?
tubercle bacillus
Koch formulated this criteria that provided proof that a specific bacterium caused a disease
Koch’s Postulates
The causative agent must be present in every case of the disease and must not be present in healthy animals.
Postulate 1
The pathogen must be isolated from the diseased animal hos and must be grown in pure culture.
Postulate 2
The same disease must be produced when microbes from the pure culture are inoculated into healthy susceptible animals.
Postulate 3
The same pathogen must be recovered once again from this artificially infected animal host, and it must be able to grow again in pure culture.
Postulate 4
Branch of Biology dealing with the study of microbes
Microbiology
Microbiology further branches into:
Bacteriology
Virology
Mycology
Parasitology
Imunology
Study of bacteria
Bacteriology
Study of viruses
Virology
Study of fungi
Mycology
Study of parasites
Parasitology
Study of cells, molecules and mechanisms responsible for immunity
Immunology
They are minute unicellular organisms that have all the necessary protoplasmic equipment for growth and self-multiplication at the expense of available foodstuff
- may be normal flora or pathogenic in human
Bacteria
They do not have a sexual growth cycle but some produce asexual spores
Bacteria
They are obligate intracellular parasites that contain either RNA or DNA and that these proteins are enclosed by capsid
Virus
Bacteriophage
Virus
They can exist as a yeast or a mold; if they can exist in both forms, they are said to be dimorphic and have both sexual and asexual reproduction
Fungi
Its growth cycle consists of vegetative and reproductive phase
Fungi
These include flagellates, amoebae, sporozoans, nematodes, trematodes, and cestodes
Parasites
Area of biologic science comprising of 3 districts but highly interrelated disciplines that includes classification, nomenclature and identification
Microbial Taxonomy
Organization of microorganisms that share similar morphologic, physiologic and genetic traits into specific groups or Taxa
Classification
The most basic taxonomic group and may be defined as a collection of bacterial strains that share many common physiologic and genetic features and as a group differ notably from other bacterial species
Species
Subgroups within a species
Subspecies
Designation given to groups below the subspecies level that share specific but relatively minor characteristics
Biotype, Serotype, Phagotype
Comprised of different species that have several important features in common but differ sufficiently to still maintain their status as individual species
Genus
The naming of microorganisms according to established rules and guidelines provide the accepted labels by which organisms are universally recognized
Nomenclature
What system does the nomenclature have?
Binomial system
Process by which a microorganism’s key features are dileneated
Identification
What do you do after which a microorganism is identified?
The profile is compared with those of other previously characterized microorganisms to be classified (taxa, genus, species)
The general characteristic categories of ID method
Genotypic characteristics & Phenotypic Characteristics
They relate to an organism’s genetic make-up including the nature of the organism’s genes and constituent acids
Genetic Characteristics
Criteria of genotypic characteristic
DNA base composition ratio
Nucleic acid base sequence analysis/ Homology
DNA is comprised of 4 bases. This criteria extent to which the DNA of 2 organisms is made up of cytosine and guanine relative to their base content can be used as an indicator of relatedness
DNA Base Composition Ratio
Base sequence extent to which sequences are similar (homologous) bet. 2 organisms can be determined directly or indirectly.
The degree of similarity of base sequence is a measure of the degree of organism relatedness.
Nucleic Acid Base Sequence (Homology)
What technique that cause a double stranded molecule to break the hydrogen bonds between its complementary strand?
Heating
What technique causes the hydrogen bonds to reunite to form a double stranded molecule identical to the original double strand?
Cooling
A method that applies the cooling technique to separated DNA strands from 2 DIFFERENT organisms to determine the extent of similarity between the base sequences of the 2 organisms
Nucleic Acid Hybridization
Nucleic Acid Hybridization assumes that a major portion of the nucleic acid sequence will also be similar in measuring the ability of the DNA strands to hybridize with the other organism.
If the 2 species are similar or related
The greater the degree of hybridization
The greater the degree of relatedness
Based on features beyond the genetic level and includes readily observable characteristics and those characteristics that require extensive procedures to be detected
Phenotypic Characteristics
Phenotypic characteristics criteria
Microscopic Morphology
Staining Characteristics
Environmental Requirements
Nutritional Requirements
Macroscopic Morphology
Subcellular Properties
Resistance Profiles
Antigenic Properties
Size, shape, intracellular inclusion, cellular appendages, arrangement of cells
Microscopic Morphology
Ability of the organism to grow at various temperatures, in the presence of O2 and other gases, at various pH levels, or in the presence of ions and salts such as NaCl
Environmental Requirements
Ability of organism to utilize various C and N2 sources as nutritional substrates when grown under specific environment conditions
Nutritional Requirements
Characteristics of microbial growth patterns on artificial media as observed when inspected with the unaided eye
Macroscopic Morphology
Establishment of the molecular constituents of the cell that are typical for a particular taxon, or organism group, by various analytical methods
Subcellular Properties
Exhibition of a characteristic inherent to resistance to specific antibiotic, heavy metals, or toxin by certain microorganisms
Resistance Profiles
Establishment of profiles of microorganisms by various serologic and immunologic methods that are useful for determining relatedness among various microbial groups
Antigenic Properties
Undifferentiated unicellular organisms that do not form the specialized tissues and organ systems of higher plants and animals
Protists
Higher protists
algae(red, green, brown)
fungi, protozoa, slime molds
Eukaryotes
- Contains membrane enclosed organelles that have specific cellular functions
- Have cytoskeleton which provides support for the different organelles
- Contain complex phospholipids, sphingolipids, histones, sterols
- Have multiple chromosomes and nucleosomes
- Have a mitotic apparatus
Eukaryotes
Lower protists
Bacteria
Cyanobacteria (blue-green algae)
Archaebacterial (methanogens, extreme halophiles, thermoacidophiles)
Prokaryotes
- Have no organelles, histones and only in rare cases - complex phospholipids, sphingolipids and sterols (mycoplasma)
- Have a cell wall composed of peptidoglycan with muramic acid
- Are haploid with single chromosome
- Divide by binary fission
Prokaryotes
Shape and arrangement
Size
Microscopic Morphology
The three morphological categories
Cocci or spherical cell
Bacilli or ord-like cells
Spiral organisms
When some bacteria tend to form long strands composed of many cells an occasional cell may be seen after it breaks away from a longer filament
Filamentous
When a few bacteria change their shapes are called
pleomorphic
Coccus (cocci)
diplococci
streptococci
staphylococci
tetrad
sacina
Streptococcus pneumoniae
Neisseria gonorrhoeae
Diplococci
Streptococci
Streptococcus pyogenes
Staphylococci
Staphylococcus aureus
Gaffkya tetragena
Tetrad
Sarcina lutea
Sarcina
Spherical cells
cocci
Rod-shaped cells
bacilli
Mycobacterium tuberculosis
Diplobacilli
- Slipping
- Snapping
Mycobacterium tuberculosis
Bacillus subtilis
Streptobacilli
Escherichia coli
Coccobacilli
Vibrio cholerae
Vibrio
Bacillary forms twisted in the form of a helix
Spiral forms
Campylobacter jejuni
Spirillum
Genus Treponema
Genus Leptospira
Genus Borrelia
Spirochetes
T. pallidum
Genus Treponema
L. interrogans
Genus Leptospira
B. recurrentis
Genus Borrelia
u =
um =
micra
micrometer
1um
1/1000 of a mm
or
1/25000 of an inch
0.4-2um
Cocci
0.2-4um in width by 0.5-20um in length
ex. Haemophilus influenza, Bacillus anthracis
Bacilli
1-14um in length
Spirals
