Lab2: 1-16 except 14 Flashcards
factors that affects resolution, shorter the wavelength of light used, ___________.-white light used in compound microscope limits resolution of structures smaller then 0.2mm
higher resolution
higher magnification inverse relationship to _________.
lower resolution
the objective lens magnifies the specimen to produce ____1_____ that is projected to ocular lens to produce the _____2_____.
1.real image2.virtual image
list 4 points regarding proper use and storage of microscopes. “just remember”
- use both hands when you carry a microscope to your table.2.plug in the lamp cord into electrical outlet, then turn on the main switch of microscope3. before storing microscope back, replace the low objective lens into working position4. always check before change objective lens to avoid slide breakage.
identify at least 4 differences between prokaryotes and eukaryotes.
prokarytoes:-non membranous-one circular chromosome-divided by binary fission-made of peptidoglycanEukaryotes:-separated from cytoplasm-both membranous & non-membranous-no peptidoglycan-divided by mitosis
what is the biochemical basis of cheek cell staining process, are the cheek cells prokaryotes or eukaryotes?
methylene blue is used to stain animal/human cells to make nuclei more visible under a microscope.-the cheek cell is a eukaryote, because eukaryotic cell contain a nucleus.
Staining:define primary stain
mainly stain all cells
Staining:define mordant
holds the dye down
Staining:define decolorizing
wash of primary stain
Staining:counterstain
color to cells that dont retain the primary stain
describe the principle of gram’s staining process, include the role of each chemical reagent used in the staining process.
To distinquish between two cell wall gram positive and negative.
advantages of the gram’s staining process
advantage:-it’s a relatively rapid and an extremely useful tool-the staining provides suggestive includes during the identification process-it provide valuable information so as to initiate course of antimicrobial treatment
disadvantages of the gram’s staining process
disadvantage:-often, disease causing bacteria, does not have distinct stain characteristic -the stain is not specific enough to diagnose the cause of most infection-some bacterial cells stain poorly or not at all
list 3 precaution for the gram’s stain
1.fixing2.staining3.timing
identify the 2 bacteria’s which characteristically produce spores. name the bacteria you did for that experiment.
1.spore has a thick wall2.is a metabolically inactive structureBacillus anthrasis or Clostridium tetanus
what is 5 features of spores and list spore position inside vegetative cells
- spore begin to isolate DNA replicate2. plasma membrane surround DNA3. spore septum surrounds isolated portion forming forespore4.peptidoglycan layer forms between membrane5.spore coat forms then endospore freed from cell
what are functions of spore?
are reproductive cells that must fuse in pairs in order to give rise to a new individual.
what are differentiate between spore and vegetative cells?
- endospores is form from vegetative cell2.vegetative cell response to environment signals
what is sporulation and germination?
1.sporulation- process of spore formation in a sequential event2.germination - bacterial spore transform into a vegetative cell upon return of favorable conditions by the metabolic process
name 2 bacteria’s which are acid fast positive and the associated disease they cause in humans.
Mycobacterium nocardia>Mycobacterium tuberculosis - causes chronic diseasesMycobacterium leprae - hansen’s diseases
describe the composition of the cell wall that is responsible for the acid fast properties of the cell.
Acid Fast Bacteria are Gram positve, peptidoglycan contain large amout of lipids (mycolic acid).
What is sterile transfer technique?
they incorporate procedures that minimizes chance of other organisms being accidentally introduced.
list 4 factors with regard to importance of the sterile transfer techniques.
- free from containing you or others2. prevent culture from contaminating you or others3.to isolate pure culture of microbes not considered4.prevents observing features of microbes
name 2 methods for pure culture isolation.
1.spreading plating on solid agar medium with a glass spreader.2.streaking plating with a loop
list 3 common errors in colony isolation by the streak process
1.label all media, tubes and cultures2.use a loop which is sufficiently cooled3. avoid aerosols4. disinfects work place
why pour plate technique needs to be done at a faster pace compared to the streak plate method
pour plate needs to be cooled enough before it solidify while streak plate doesn’t
what is peritrichous arrangement of flagella?
peritrichous - Multiple flagella may be randomly distributed over the entire bacterial cell
what is amphitrichous arrangement of flagella?
amphitrichous - A single flagellum (or multiple flagella; see below) can extend from both ends of the cell
what are spirochete?
are flexible, is a member of the phylum Spirochaetes, which contains distinctive diderm bacteria, most of which have long, helically coiled cells
name the disease that caused by the spirochete Borrelia burgdorferri
predominant causative agent of Lyme disease
Acid Fast Positive -
Clumped together “cord factor” virulence factor (red in color due to carbolfuschin)
Non-Acid Fast (negative) -
blue in color due to methylene blue
emb plate contain
lactose sugar, peptones, sodium deoxycholate, eosin, methylene blue, extracted best yeast
Lysozyme is an ezyme found in body’s secretion, such as ___1___,____2____,____3_____ and ____4___.
- saliva, 2. nasal secretion, 3. tears and
- hen’s egg(only the concentratedwhite part)
Lysozyme hydrolyzes the glycosidic bond between the ____1____ units of bacterial cell wall. which can cause the bacterial cell to ____2____.
- NAG-NAM (backbone components)
- Osmotic bursting
Lysozyme action is more pronounced and clear in Gram ___1____ than Gram ___2_____
- Gram Positive
- Gram Negative
Gram _______ cells susceptibility to lysozyme action is due to lack of a Protective barrier to the peptidoglycan layer.
Gram positive
In Gram ______ cells have an outer membrane which covers the peptidoglycan layer and shields from enzymatic attack of lysozyme
Gram Negative
__________ and __________, they represent media which routinely used by microbiologist to isolate, identify and confirm presence of specific microorganism from specimen or environment
Starch hydrolysis test:
Selective and differential media
______ have components that inhibit the growth of unwanted bacteria and encourage growth of desired microorganism. Example: Thayer Martin media,Sabouraud’s dextose Agar
Starch hydrolysis test:
Selective media
________ designed for easier detection and isolation of microorganism of interest from other growing on the same plate. Often a particular trait of the microbes is exploited
Starch hydrolysis test:
Differential media
EMB Agar, Mannitol salt Agar and Mc Conkey Agar are both ________ and _______ media
Starch hydrolysis test:
Selective and differential
_______ is a complex carbohydrates (polysaccharide), observed as inclusion bodies in some bacteria.
Starch hydrolysis test:
Starch
______ serves as carbon and energy reserve and can be degraded into individual glucose units and metabolized
Starch hydrolysis test:
Starch
If Bacteria are cultured on media containing starch as sole sugar source, some synthesize and secretes an enzyme called _______
Starch hydrolysis test:
Amylase
_______ belongs to the class of exoenzyme and breaks down starch so individual glucose unit can be transported inside cell easily.
Starch hydrolysis test:
Amylase
The ability to break down starch is examined using ________, it detects presence or absence of intact starch around Bacterial growth area
Starch hydrolysis test:
Iodine reagent
If starch is broken vicinity of bacterial growth, there would be…..
Starch hydrolysis test:
No reaction of iodine with starch
In starch hydrolysis test, Indication of starch hydrolysis by amylase, is seen as a __________ around bacterial growth
Starch hydrolysis test:
Clear area (halo)
In starchhydrolysis test, If intact starch is observed as ___________ around colony which indicate as non-hydrolysis
Starch hydrolysis test:
Blue Color/Dark coloration
_______ is an enzyme produced by many microbes to neutralize the toxic effect of hydrogen peroxide.
Catalase Test:
Catalase
Catalase breaks down hydrogen peroxide to generate ______ and _________.
Catalase Test:
water and oxygen
In catalase test, oxygen release from the peroxide molecule is abserved as ________. immediate ______ is indicative of positive catalase test
Catalase Test:
Bubble
bubbling
Bacterial cells growth is influenced by many ______ and ________ factors
Anaerobic bacterial growth/Gas Chamber:
physical and chemical
______ and chemical factors are required at specifc levels; any deviations from their normal levels and conditions compromises severely bacterial growth
Anaerobic bacterial growth/gas chamber:
Physical and chemical
In anaerobic chamber, available oxygen is depleted due to chemical reactions which are initiated by ________.
Anaerobic bacterial growth/gas chamber:
adding water
The bacteria Clostridium sporogenes is a aerobic or anaerobic?
Anaerobic bacterial growth/gas chamber:
Anaerobic
the bacteria Bacillus subtiles a aerobic or anaerobic?
Anaerobic bacterial growth/gas chamber:
aerobic
The bacteria staphylococcus epidermidis is aerobic or anaerobic?
Anaerobic bacterial growth/gas chamber:
aerobic
________ is primarily used to differentiate enterics from nonenterics gram negative bacilli.
TSI agar (triple sugar iron)
_____ a complex, enriched medium with 3 sugars (glucose, sucrose and lactose).
TSI agar (triple sugar iron)
In TSI agar (triple sugar iron), _______ is supplemented at the low range concentration (0.1%) compared to the other 2 sugars.
Glucose
TSI agar (triple sugar iron) Medium differentiates bacteria on the basis of ______ Fermentation and ______ Reduction.
Sugar fermentation and sulfur reduction
TSI agar (triple sugar iron) media that has a deep butt is ________.
anaerobic condition
TSI agar (triple sugar iron) media that has a shallow slant is ______. due to Na2S2O3–>H2S
aerobic condition
In TSI agar (triple sugar iron) media yellow slant/butt, ______, _______, and/or _______ fermentation with acid accumulation in slat and butt.
This detects bacteria E.coi and Enterobacter aerogenes which also contain gas production due to cracks and lifting agar.
Glucose and lactose and/or sucrose
In TSI agar (triple sugar iron) media Red slant/ Red Butt, No Fermentation. _______ catabolized aerobically and anerobically with alkaline products. if its a Red Butt, is most likely a Obligate aerobe.
This detects bacteria Pseudomonas aeroginosa
Peptone
In TSI agar (triple sugar iron) media Black precipitate in the gar, _____ reduction. Hydrogen sulfide (H2S) maybe produced by the reduction of _________ in the medium.
This detects bacteria Proteus mirabilis, also have a red slant which due to glucose.
Sulfer Reduction
thiosulfate
______ physical factor is used extensively for microbial growth control. most vegatative cells of microbes exhibit differences in their _____ tolerance. _______ can be in the form of moist _____ or dry ________.
Control of microorganisms:
Heart
______ is used in, pasteurization process (milk and juices), autoclaving of surgical materials and sterilization of baby’s feeding bottles.
Control of microorganisms:
Moist heart
________ can be used to kill microbes, sterilization of microbiological inoculating loop in lab.
Control of microorganisms:
Dry Heart
________ form of cells get killed by moist heart.
Control of microorganisms:
Vegetative
During control of microorganisms Moist Heart lab, the bacteria ___1____ did not grow, but ____2____ and _____3__ have grown from 5-25min.
- E.coli
- staphylococcus epidermidis
- bacills cereus
____1_____ is a method that incorporates mechanical removal of microorganisms from samples. the method involves passage of a liquid through a screen like material of ___2_____.
- Filter sterilization
- high tensile strength
In filter sterilization, the filter paper is inert; is made of _________ or ________.
Nitrocellulose or PVDF
In filter sterilization, Heat sensitive preparations of antibiotic, glucose, vaccines, ophthalmic soulution and enzymes are made ___1____. the pore size of the membrane is variable; we will use membrane with pore size of ___2___.
- free of microbes (sterilized)
- 0.45um
In filter sterilization, uses filter water sample to evaluate presence of coliforms, it yields accurates results if the colony count is in range of ______ organisms per filter disces. filtration can be used on emb plate or agar plate
30-300
