Exam 1 Flashcards
This man was the first to develop a lens powerful enough to view microbes
Antonie van Leeuwenhoek
This man was the first to demonstrate a connection between a single isolated microbe and known human disease
Rober Koch
Modern taxonomy relies heavily on
Comparing the nucleic acids (DNA or RNA) or proteins from different organisms
_____ ____ created a tree with three domains above the level of kingdom
Which included
Carol Woese nnnnnar
Archaea
Bacteria
Eukarya
The genus part of the name is always
capitalized
followed by the epithet name (not capitalized)
always italicized
Microorganisms are found in each of the three domains of life:
Archaea
Bacteria
Eukarya
Bacteria and Archaea are ______ (their cells lack a nucleus)
prokaryotes
Eukaryotes have or do not have a nucleus?
DO
Bacteria are prokaryotic because their genetic material DNA is _____ housed within a true nucleus
NOT
Common bacteria shapes include:
Bacillus
Coccus
Spirillum
Spirochete
Vibrio
______ are also unicellular prokaryotic organisms
Archaea
______ are found in nearly every habitat on earth, even extreme environments
Archaea
The domain Eukarya contains all eukaryotes, including uni- or multicellular eukaryotes such as :
Protists
Fungi
Plants
Animals
Two examples of Protists are
Algae and Protozoa
Protists such as ____ can be unicellular or multicellular
Algae
______ move with help from hair like structures called cilia and flagella and pseudopods (false feet)
Protozoa
Yeasts are multicellular or unicellular fungi?
Unicellular
Multicellular parasitic worms called
Helminths
______ are acellular microorganisms which means they are not composed of cells.
Either DNA or RNA but never ______
Viruses
Both
Refraction occurs when
Light waves change speed and direction as they pass from one medium to another
The power of a microscope can be defined in terms of its
Magnification and Resolution
A _____ microscope has a much higher resolution than a light microscope since it uses an electron beam with very short wavelength.
Electron
__________ was credited with the first observation of microbes
Antonie van Leeuwenhoek
Was the first to describe cells ( looked at dead cork cells )
Robert Hooke
Uses lenses to focus light on specimen to produce and image
Light Microscopy
Produce a dark image on a bright background
Brightfield
Total magnification =
Ocular magnification x Objective magnification
____ scatters the light rays
Air
_____ can be used to fill the space between the specimen and an oil immersion lens
Oil
Oil has the refractive index very similar to _____ thus increasing the light collected and resolution of the image
glass
Shows bright objects on a dark background
Darkfield
_______ is useful for viewing live specimens without the use of stains
Darkfield
_____ use refraction and interference to create high contrast and high resolution images WO staining
Phase contrast
____ _____ ____ use interference patterns to enhance contrast between different features of a specimen using two beams of light
DIC
Differential Interference Contrast
Absorb energy from light source then emits this energy as visible light
Fluorescence
Microscopy technique that is used to identify certain disease causing microbes by observing whether antibodies bind to them.
Immunofluorescence
uses a laser to scan multiple z planes successively
Confocal
_______ microscopy focuses electrons on the specimen using magnets.
Uses short wavelength electron beams rather than light.
Electron
_____ _____ _____ requires that the beam and specimen be in a vacuum and that the specimen be very thin.
Transmission Electron Microscope (TEM)
____ ____ ____ form images of surfaces of specimens
Scanning electron microscope (SEM)
____ ____ ____ produces images of even greater magnification by measuring feedback from sharp probes that interact with the specimen.
Scanning probe microscopy
Two types of microscopes that observe individual atoms on surfaces
Scanning tunneling microscope
Atomic force microscope
___ ____ ____ to properly prepare a slide for microscopy.
Smear
Heat fix
Stain
___ ____ (acid stains) absorbed by the background not by the negatively charged cell.
Produces a silhouette of the organisms against a _____ background
Negative stains
Colorful
___ ____ (basic stains) stick to the cell walls of negatively charged cells
Positive cells
Two types of staining:
Simple (one stain)
Differential (two stains)
Crystal violet, a primary stain, is applied to a heat fixed smear, giving all of the cells a ______ color
Purple
_____ _____ (a substance used to set or stabilize stains or dyes) in this case, it traps the cystal violet in the cell by making the complex clump
Gram’s Iodine
___ _____ (ethanol or an aceton solution) Cells with thick peptidoglycan layers ( Gram Positive Bacteria) are less affected and retain the crystal violet dye and remain ______.
Decolorizing agent
Purple
The decolorizing agent more easily washes the crystal violet out of cells with thinner peptidoglycan layers in gram negative bacteria leaving them _______
colorless
_____ ______ (_____) is added. This stains the decolorized cells pink and is less noticeable in the cells that still contain the crystal violet dye.
Secondary Counterstain (safranin)
The purple, crystal violet stained cells are referred to as _________ while the red safranin dyed cells are ________
Gram positive
Gram negative
________ bacteria tend to be more resistant to certain antibiotics than _______ bacteria
Gram negative
Gram positive
____ ______: a negative staining technique
Capsule staining
Acid fast staining ______ ____ is the primary stain
Waxy acid fast cells retain the carbol fuchsin even after a _____ _____ is applied.
____ ___ is then applied which renders non acid fast cells blue
Carbol Fuchsin
Decolorizing agent
Secondary counterstain, methylene blue
- Uses heat to push the primary stain into the endospore
- Washing with water decolorized the cell, but endospore retains green stain.
- Cell is then counterstained pink with safranin.
Endospore staining
Endospore staining techniques are important for identifying ____ and _____
Bacillus and Clostridium
_______ ______: life arose from nonliving matter
Spontaneous generation
______ _____ disproved the theory of spontaneous generation with his famous swan neck flask experiment
Louis Pasteur
____ _____ proposed that “life only comes from life”
Louis Pasteur
Cell theory (cork under a microscope)
Robert Hooke
“all cells arise from cells”
Rudolf Virchow
_________ theory states that mitochondria and chloroplast have their origins in bacteria.
Endosymbiotic
Eukaryotic organelles (mitochondria and chloroplasts) are of prokaryotic origin is the hypothesis created by
Lynn Margulis
_______ and _______ are structurally similar to bacterial ribosomes, rather than to the eukaryotic ribosomes of their hosts.
Mitochondrial
Chloroplasts
Binary fission of these two organelles strongly resemble binary fission of bacteria as compared with mitosis performed by eukaryotic cells.
Mitochondria
Chloroplasts
Germ theory of disease
Diseases may result from microbial infection
Founder of the Germ Theory
Louis Pasteur
____ ____ began using carbolic acid (phenol) spray during surgery
Joseph Lister
______ proposed the cause of a specific disease could be attributed to a specific microbe.
Robert Koch
______ _____ occurs because of differences in the concentration of solutes on opposing sides of a semipermeable membrane.
Osmotic Pressure
For ______ and _______ their genetic material is contained in a _____ rather than a membrane bound nucleus.
Bacteria and Archaea
________ cells lack membrane bound organelles
Prokaryotic
Prokaryotic cells may contain extrachromasomal DNA in _______ which often carry genes such as antibiotic resistance.
Plasmids
______ ____: site of protein synthesis and have size of _____
Prokaryotic ribosomes
70S
Clinically significant Gram-Positive bacteria that can form endospores:
Bacillus
Clostridium
Cell envelope =
Plasma membrane + cell wall
______ ____ are composed of phospholipids
Plasma membranes
Prokaryotic cell walls may be composed of ______ (found only in bacteria)
Peptidoglycan
_____________ bacterial cells are characterized by a thick peptidoglycan layer
Gram Positive
_________ bacterial cells are characterized by a thin peptidoglycan layer surrounded by an outer membrane.
Gram negative
______ contribute to a microbes pathogenicity (ability to cause disease) which makes it more difficult for _______ cells (WBC) to engulf and kill them
Capsules
Phagocytic
_____ are typically more numerous and shorter
Fimbriae
____ are larger and less numerous than fimbriae
Pili
_____ are important in the transfer of genetic material between cells
Pili
______ flagella that cover the entire surface of a bacterial cell
Peritrichous
______ one end of the cell (polar)
Monotrichous
Flagellum or tufts of flagella at each end
Ampitrichous
Tuft at one end of the cell
Lophotrichous
______ cells have a nucleus bound by a nuclear membrane
Eukaryotic
Eukaryotic cells contain _____ ribosomes
80S
_______ ribosomes in mitochondria and chloroplasts.
70S
_______ _____ membrane bound organelles involved in transport.
Endomembrane system
___ ____ ____ : lipid biosynthesis, carbohydrate metabolism, and detoxification.
Smooth endoplasmic reticulum
____ ____ ____ contains membrane bound 80S ribosomes that synthesis proteins
Rough Endoplasmic Reticulum
Endomembrane system includes:
Endoplasmic reticulum
Smooth endoplasmic reticulum
rough endoplasmic reticulum
processes proteins and lipids
Golgi apparatus
Contain digestive enzymes
lysosomes
Site of cellular respiration
Mitochondria
Eukaryotic cell membranes can take material in to the cell via _____ or expel matter from the cell ____
Endocytosis
Exocytosis
Types of Endocytosis
Phagocytosis
Pinocytosis
Cell eating
Phagocytosis
Cell drinking
Pinocytosis
Fungi, algae, plants and some protists have a
Cell wall
Types of cell walls
Cellulose (fungi and plants)
Chitin (fungi)
____ and ____ are unicellular prokaryotic organisms.
Archaea and Bacteria
_________: the totality of forms of prokaryotes (particularly bacteria) living on the human which varies between regions of the body and changes over time
Microbiome
_______ : the totality of forms of prokaryotes living in a certain region of the human body
(primarily bacteria)
Microbiota
Two types of microbiota include
Resident and Transient
____ microbiota constantly live in or on our bodies
Resident
_____ microbiota is temporarily found in the human body.
Transient
_______ colonization during vaginal child birth
Demonstrating a higher incidence of diseases in individuals born by c-section compared to those born vaginally
Lactobacillus
Gram positive bacteria are classified based on their prevalence of _____ and ____ nucleotides
Guanine and cytosine
Gram negative bacteria are classified:
Spriochetes
Proteobacteria
Atypical
Mycoplasma
SPAM
_____ bacteria cannot be stained by the standard gram stain procedure
Atypical
Proteobacteria are further classified into the classes
Alpha
Beta
Gamma
Delta
Epsilon
Rickettisia
R.rickettsii: causes
Rocky Mountain spotted fever spread by ticks
Betaproteobacteria include
Neisseria
N. gonorrhoeae
N. meningitides
Bordetella pertussis
_____ causes the STI gonorrhea
N. gonorrhoeae
_____ causes bacterial meningitis
N. meningitides
____ causes pertussis ( whooping cough)
Bordetella pertussis
_______ are the largest and most diverse group of proteobacteria
Gammaproteobacteria
_____ often infects wounds and burns
Pseudomonas aerugionsa
Haemophilus
H. influenzae: (does not cause influenza) Can cause both upper and lower respiratory tract infections including
Sinusitis
Bronchitis
Ear infections
Pneumonia
Vibrionales include
Vibrio cholerae
and
V. vulnificus
_____ causes cholera
Vibrio cholerae
____ causes serious and potentially life- threatening cellulitus
V. vulnificus
Escherichia coli
Salmonella
Shigella
yersinia pestis
are all types of
Enteric Bacteria
______ is the most studied bacterium
Escherchia coli
____ causes typhoid fever
Salmonella
________ is the most common cause of chronic gastritis and ulcers of stomach and duodenum, also linked to stomach cancer
Helicobacter pylori
Spiral bacteria with a long narrow body
Spirochetes
________ contain human pathogens that cause diseases such as syphilis and lyme disease.
Spirochetes
________ bacteria are a group categorized by their ability to use the energy of sunlight
Phototrophic
_______ are oxygen producing bacteria thought to have played a critical role in the forming of the earths atmosphere
Cyanobacteria
_______ ____ causes diphtheria, produces a toxin that forms a pseudomembrane in the patients throat causing swelling, difficulty breathing.
Corynebacterium diphtheiae
_____ ______ can cause bacterial vaginosis in women
Gardnerella vaginalis
______: bacilli covered with a mycolic acid coat
This waxy coat protects the bacteria from some antibiotics
Mycobacterium
_____ cause tuberculosis
M. tuberculosis
______: leprosy
M. leprae
___________ generally obligate anaerobes and can form endospors
Clostridium spp.
________(gas gangrene)
C. perfringens
_______ (tetanus) produces a neurotoxin that is able to enter neurons, travel regions of the central nervous system where it blocks in inhibition of nerve impulses.
C. tetani
______ (botulism) produces botulimum neurotoxin the most lethal biological toxin known
Blocks the release of acetylcholine causing flaccid paralysis
C. botulimum
____ is a common source of hospital acquired infections
C.difficile
_____ the most common cause of bacterial pharyngitis (strep throat)
S. pyogenes
________ :Cells appear as diplococci and causes pneumonia
S. pneumoniae
Staphylococcus
S. aureus strains can cause a wide range of infections and diseases
Many of which are highly resistant to antibiotics like
MRSA
VRSA
_____ are very small and lack cell walls
Mycoplasma spp.
______ are unicellular, prokaryotic microorganisms
Also differ structurally from bacteria in several significant ways.
Archaea
Some _____ are extremophiles living in environments
Archaea
______ archaea prefer a concentration of salt
Halophilic
______ is the most common human intestinal parasite in the US
Giardia
______ diarrheal illness that is easily transmitted through contaminated water supplies
Giardiasis
Protists were informally grouped into
“animal like”
“plant like”
“fungus like”
Nonphotosynthetic, motile organisms that are always unicellular
Protozoans
animal like
_____: photosynthetic organisms that can be unicellular or multicellular
plant like
algae
____ protists such as water molds
fungus lke
Protozoans that reproduce Asexually
Binary fission
Budding
Schizogony
Protozoans that reproduce sexually
Syngamy
Conjugation
_______ brain eating amoeba
Naegleria fowleri
________: individual amoeboid cells that periodically aggregate into a mobile slug
Cellular slime molds
_____: exist as large, multinucleate amoeboid cells that form reproductive stalks to produce spores that divide in to gametes
Plasmodial slime molds
_______: intra- or extracellular parasites
Apicomplexans
cause of malaria
Plasmodium
_____ _____ causes intenstinal symptoms and can cause epidemic diarrhea when the cysts contaminate drinking water
Cryptosporidium parvum
______ _______ transmitted by the tick
causes recurring fever that can be fatal and is becoming a common transfusion transmitted pathogen in the US
Theileria (Babesia) microti
____ _____:: causes toxoplasmosis and can be transmitted from cat feces
Can be associated with serious birth defects
Pregnant women should be aware of risk if exposed to cat feces
Toxoplasma gondii
____ ____: widespread pathogen that cuases diarrheal illness spread through cysts feces that contaminate water supplies
Giardia lamblia
_____ ______ causes the human sexally transmitted disease trichomoniasis.
Often does not cause symptoms in men but men are able to transmit the infection
Trichomonas vaginalis
_____ _____ which causes African trypanosomiasis (African sleeping sickness)
Colonizes the blood and the brain after being transmitted via the bite of a tsetse fly
Trypanosoma Brucei
_________ Causes American trypanosmiasis (chagas disease)
transmitted by insects often called kissing bugs
T. cruzi
_____ common intestinal parasites often tansmitted through undercooked foods
Roundworms
Two types of helminth parasites are
Roundworms
Unsegmented worms
______ ______ (pinworm) is the most common nematode infection in the US
Enterobius vermicularis
_____ and _____ are nematodes found in dogs and cats that can be transmitted to humans
Toxocara canis
T. cati
_____ ____ the New World or North American hookworm
Necator americanus
_____ contracted by consuming undercooked meat
Trichinella spiralis
_____ _____ causes heartworm in dogs and other animals
Dirofilaria immitis
Species that can cause mycoses
Pathogenic
_____ are unicellular fungi
Yeasts
Associated with vaginal yeast infections oral thrush and candidasis of the skin
The most common cause of vaginal and other yeast infections
Candida albicans
Ringworm is a _____ not a worm
Fungus
________ are acellular and consist of nucleic acid DNA or RNA but not both surrounded by a protein capsid.
Virons
______ _______ formed from only a nucleic acid and capsid
naked viruses
____ _____ nucleic acid packed capsid surrounded by a lipid layer
enveloped viruses
_____ are obligate intracellular parasites
viruses
The viruses that infect bacteria are called ______
Bacteriophages
__________ spikes help the influenza virus attach to host cell
hemagglutinin_
_________ allow the virus to detach from the cell surface during release of new virions
neuraminidase
In the life cycle of bacteriophages: _______ leads to the death of the host
virulent (have a lytic cycle)
In the life cycle of bacteriophages _____ leads to integration of the phage into the host genome
Temperate (have a lysogenic cycle)
Integrated phage genome is called a
prophage
Life cycle of viruses with Animal hosts
Attachment
Penetration
Uncoating
Biosynthesis
Maturatioin
Reslease
HIV carry a special enzyme called r
Reverse transcriptase
The integrated viral genome is called a
Provirus
Animal viruses are detected by:
Hemagglutination assay
Hemagglutination inhibition assay
