Microbiology Exam 1 Flashcards
Microbiology
scientific study of microorganisms & their effect on other living organisms; literally, the study of small life.
Divisions of Microbiology
Bacteriology Rickettsiology Virology Protozoology Mycology
Bacteriology
study of bacteria;
Rickettsiology
study of rickettsia
Virology
study of viruses,or viral diseases
Protozoology
study of protozoa *the smallest form of animal life
Mycology
study of fungi (yeasts & molds)
Bacteria
a prokaryotic one-celled mircoorganism of the Kingdom Monera, existing as free living organisms or parasites, multiplying by binary fission and having a large range of biochemical properties staph., strept., infections
Mycoplasmas
bacteria of the Mycoplasma genus that are found in humans have no cell wall; the smallest free-living organisms; size between viruses & bacteria, famous in humans for causing an infection called primary atypical pneumonia;
Rickettsia
a genus of gram-negative, pathogenic, intracellular parasitic bacteria, febrile infections (named for person discovering it Sr. Anthony Ricketts) Could run a fever of 107 degrees-Rocky Mountain Spotted Feverfebrile infections, mostly spread by insect; ex. typhus fever The infection accompanying these is high fever and last a longer period of time. Flea born or rat also transmitted by louse or lice
Chlamydia
a large group of nonmotile, gram negative intracellular parasites; parrot fever, NGU (non gonococcal urethritis) leading sexually transmitted disease
Viruses
smallest microorganism know; measles, mumps, flu, hepatitis, smallpox must use an electron microscope to see virus/ virus cannot live alone *this is the smallest microorganism known to man.
Protozoa
smallest form of animal life, malaria, amebic dysentery one celled organisms of the Kingdom Protista-most are unicellular although some are colonist
Fungi
yeast and molds; athlete’s foot, thrush, PCP, a group of diverse and widespread unicellular and multicellular organisms lacking chlorophyll, usually bearing spores and often filamentous
Prion
small proteinaceous infectious agents (particles) which almost certainly do not have a nucleic acid genome and therefore resist inactivation by procedures that modify nucleic acids.(Ex: Creutzfeldt-Jakob (CJ) )
Which family or group of microorganisms cause the greatest majority of infection in man?
Bacteria
Morphology
study of external structure and form without regard to its function
Taxonomy
classification or naming of all living things
Dimorphism
ability to exist in either one cell or multi cell form
Phagocytosis
Cell ingestion, white blood cells destroy foreign objects
Virulence
likelihood disease causes infection to human from a microorganism; relative power of an organism to produce disease
Micron (L)
largest unit of measure 25,000 of an inch
Nanometer (M)
medium unit of measure 250,000 of an inch
Angstrom (S)
smallest unit of measure 2.5 millionth of an inch
what are the 3 main shapes of bacteria?
- Spherical
- Rod
- Spiral
Coccus (pl. Cocci)
spherical (round) or ovoid shaped bacteria
Bacillus (pl. Bacilli)
rod (capsule) shaped bacteria
Spirillum (pl. Spirilla)
spiral shaped bacteria
Vibrio
(L. to move rapidly, vibrate) a genus of spiral bacteria which are curved or bend rods that resemble commas Example: Cholera
Spirillum
a genus of spiral bacteria having a snake shape with a rigid cell wall and hair-like projections called flagella that assist in movement;
Spirochete
a genus of bacteria having a flexible cell wall but no flagella in the traditional sense. Movement in these organisms occurs by contractions (undulating) of long filaments (endoflagella) that run the length of the cell; corkscrew shaped bacteria (Syphilis)
What are the 3 arrangements of Cocci
- Diplococci
- Staphylococci
- Streptococci
Diplococci
pairs meaning only 2; a variation of round shaped bacteria
Staphylococci
a genus of gram positive, nonmotile, opportunistic bacteria which tent to aggregate in irregular round clusters; bunches like grapes
Streptococci
spherical shaped bacteria occurring in chains-
What are the 2 arrangements of Bacilli
- Diplobacilli
2. Streptobacilli
Diplobacilli
a double bacillus, two being linked end to end. Morax-Axenfeld bacillus a cause of conjunctivitis is typical of this form.
Streptobacilli
rod-shaped bacteria occurring in chains
Cell wall
the outermost layer which gives shape and integrity (strength) to bacteria; its makeup used to differ among microorganisms; Ex: high lipid (fat) for TB; protein in gram stain (blue if yes, red if no) This test shows if there is protein in the bacteria of TB
Cell membrane
a thinner, inner layer; controls entry and exit into the bacteria
Cytoplasm
living substance present in the cell
Capsule (slime layer)
the membrane that surrounds some bacterial cells; a loose gel-like structure that, in pathogenic bacteria helps to protect cells from phagocytosis, thus enhancing virulence of microorganism
Endospore
a thick-walled spore within a bacterium; best means of protection any microorganism can possess; NOT a means of reproduction, means of survival, never more than 1 per cell
What are the only 2 genus that are able to form endospores?
- Bacillus
2. Clostridium
Vegetative Bacteria
any bacteria that can never form endospores; or any bacteria which can produce endospores, but is NOT currently
Sporilating Bacteria
any bacteria which is currently producing endospores; occurs under adverse living conditions
Germinating Bacteria
when free, endospores forms new vegetative cell when good living conditions return
Flagella
used for movement of bacteria; long whip-like structures attached to outside
Monotrichous
form of flagella; single long tail like (ex. sperm)
Peritrichous
form of flagella; several hairs like all around
Pili
“little hairs” shorter than flagella and used to aid in attachment to the initial site of infection (ex. gonorrhea)
Bacterial typical reproduction is by?
binary fission (simple transverse division) an asexual means
Binary fission
a method of asexual reproduction involving halving of the nucleus and cytoplasm of the cell followed by the development of each half into a new individual.
asexual reproduction
has everything it needs to reproduce on its own.
Bacterial colony
a visible group of bacteria growing on a solid medium, presumably arising from a single microorganism (nutrient broth, blood agar)
What are the conditions affecting bacterial growth?
- Food requirements
- Oxygen requirements
- Moisture (water) requirements
- pH
Autotrophic bacteria
self nourishing bacteria; obtain there food from an organic matter, does not contain carbon
Heterotrophic bacteria
other than self nourishing; organisms that must obtain their nourishment from complex organic matter; does contain carbon
Strict (obligate) saprophytes
an organism that can only survive on dead or decaying organic matter
Strict (obligate) parasite
an organism that is completely dependent on its living host for survival
Strict (obligate) aerobe
a microbe that can only live in the presence of free oxygen (Humans)
Strict (obligate) anaerobe
a microbe that can only survive in the absence of free oxygen (Clostridium/ Gang-green)
Microaerophilic
a microorganism that requires very little free oxygen (a level less that is required for humans)
pH
percentage of Hydrogen ion in solution; slightly alkaline for most pathogens
pH scale ranges from
0-14
pH of 7.0 is
neutral (Ex: water)
pH of 7.3-7.4
slightly alkaline; the pH of a living human body/ blood
pH of 5.0
slightly acidic; a deceased body with rigamoritis
pH of 1.0
highly acidic (Ex: HCl Hydrochloric Acid/ battery acid)
pH of 10.5
moderately alkaline
pH of 3.5
moderately acidic
pH of 13
highly alkaline (Ex: Milk)
pH above 7.0
Alkaline/ Basic turns litmis paper blue; bitter taste (bile)
pH below 7.0
Acidic turns litmis paper red (gastric juice)
Facultative saprophyte
prefers live organic matter as a source of nutrition but can adapt to the use of dead organic matter under certain conditions
Facultative aerobe
a microorganism that prefers an environment devoid of oxygen but has adapted so that it can live and grow in the presence of oxygen
Facultative anaerobe
an organism that prefers an oxygen environment but is capable of living and growing in its absence
87%
non-pathogenic
13%
can cause infection to the human body
Staph
grows in clusters (yellow pus/ golden pigment)
Strept
grows in chains
Classification of living things (highest to lowest)
Kingdom Phylum Class Order Family Genus Species
Genus
name of all living things is always Capitalized, it tells about the morphology- the external structure or form
Species
always in small letters; it tells one of the names this infection will cause. if it does not tell us an infection it causes, it usually tells us a laboratory characteristic
Staphylococcus aureus
round, clusters, golden pigment
Streptococcus pneumoniae
round, chains, infection of lung tissue (lobar pneumonia)
Neisseria meningitides
Named from person who discovered it, inflammation of 3 layer membrane in spinal cord
Hemophilus influenzae
blood living disease, flu, shingles
Borrelia burgdorferii
lime disease
typhi
typhoid fever
typhus fever
Facultative bacteria
Obtain their food from either dead or living organic matter
Spongiform encephalopathies
prion diseases & because of the post mortem appearance of the brain with large vacuoles in the cortex and cerebellum
Strep and staph are caused by
Bacteria
