Biology Unit 4 PDF

Microbial growth? mainly in bacteria Defining ? Microbial Nutrition = microbal growth Microbial population...

Microbial growth? mainly in bacteria Defining ? Microbial Nutrition = microbal growth Microbial population growth : increase the of in - in # calls a microbial population a results from cell divison Two was of ↓ in is oor ! budding ) · - Yeast (fung : binary Sission-bacteria · , aranea , Protoza Binary Fission : Basics : - two cells arise from one Parent daughter - & calls are identica - , - each daughter cell obains a copy of the Genome Steps in binary fission : 1. Chromosome duplicates.Canl 2 clongates 30 Formation of cell a cell walls membrane & septum) chromosomesessix to cytosmart on 4 Septum divides ino 3 daughter sens parent 2 Cells Separate  Generation Time & & Time required for a population of microbial Cells to double - doubling time · exponential growth Vanies from minutes to days If the & nu romere of S favorable, doubling Can Continue at a rates constant Lifestyles of Microbes 2 ways ? Pla uktonic. suspended growth liquid Coronment · in a free-floating · - does NOT attach to surfaces Ex : Liquid backers cultures growt in lab Adherent · attached to a surface · brot' ms Ex : feethPlaque - Bioflim Basics & What is it ? Adherent miccroogesisms imbedded coated in a Slimy matrix - Often more than one species of a microorganises Made of Polyaccanides , Proteins , Slime layes/capsules Does : Bind microbes cells together Advantage for the microbes - trap nutrients - Prevents detachment allows - microbes to remain in favorable & nurom ed grounds for transfer ~ Genetic · Quorum Sensing-cells Work togethe to arter the expression of the in genes ↓o Cooperate not 4 · + 4es CcuS in the Do 1 : A Bioflim formation : 19 Step attachment to Plantonic Attach surface ~ a Cars Step 313 : Colonization - extractual matex Protests, slime layers , exc is Created · this helps Cens become attached to each other Step 4 : Development Bro flims evous throug both can druison and recruit o let of ne Cells 5 : Step dispers : on - Cells leane the brotcm & colonize other areas Bio flims act 2S microbial self-defense ? resist forces - physical Slow - Penetration of art microba components ~ Protection from immune Cells - bio sims hand to treat are very & With ch the body On in dust-gl Surfaces.  Symb:0 ses : Close relat : orships bewteen Organisms that are advantageous to of least one thing in a ~ elat : 0284--p Mutualises All members Share in the benefits of & ~ lat vot shipp Commensalism : One member benef--Is from a Parnetorship While the other , , is not harmed / helped Paraitism : One member benefits and the Other is harmed. Microbes in & ↓ flim- mutual se relation shipp Environmental Effects on Microbel Growth ? Every organism adapts to their anocon went # : Camouflage Enercommental factors that infruence ↑ microbial growth ? Tempatu-e Microbes Can't control their internal temps they assome the temo of their , environmento Carding Temp? range of temps for microbial growth minioor= lowest temp that permits a microbes growth) metabolism o Maxiom - highest temp that permits a microbes growth/metabolises. Denaturation - metabolism becomes Per ougotely inactived and cell will dep Optimum-Small range of terres that Promote the fastest race of growth & metabolism. Cardinal temps Very among species · Enzyme Stability : microbes that ~ e mo sin Stable and function across a wide range of temps Survive in agriable temp environment c. Membrane fluidity Classication based on temp requirements : Psychophile : Low option temp Can't · Survive in human body I cause infections Mesophiles : Intermedige option temp medic grow the body in revelert- erry · ② 37 % Thermophile : High Option temps & Heat tolerant Oxygen : tox-c - Had > Some microbes have devolped enzymes toxic 030 to destroy forms of Microbes Ger i n to one of ↑ nese · use O2 & can detoxify it Can · neither Use Oxygen nor decurity it · Do not use O2 but can detoxify. it  Aerobe Obligate acrobe : Of is regained Facultative anacrobe : Oz iS not required , grow in its Presence om absence , acrobic respiration on for weat of 0 2 Micro derophilic Oz S ~ equired ot lowes than atmospheric concentrations Rerobic , respiration Anaerobe : Obligate anaerobe : On is foxic - fermention Aerotolerant : Do not use Oz , but can Survive it PH Organisms beween 6-8 FH PH expresses the degree of or acidity Gri of Solution a linity a Depdent 02 At and OH-ions in the Solution · O-E. 5 - acidic , Contains more Ht) Oy + · S. - S 8 : neural H = OH- 14 basic OH > H + - - 9. = arrang Effects are dependent on the PH of the microbes & durome o t Classification on microse , based on PH : Neutrophie Pit Opticer S. S-8 * c : dophite : PH optimum Prevent Contamination Protect · environments How do we Contros them : Decommination - destroy or remove microbial Contaminats Contaminato Microbes Present at a given Place (time that are vvu8 + ed Physical/Chemical Kins microbes Micobes are resistant to controls resistant not kined on inhibited by Susceptible - killed or inbibed by : 2 levels of resistance 10 Highest leasu resistance : suspectable 2. Moderate resistance 2 Least resistance = most susprexible Factors that effect deatn : time , # of minodas, nature KempR PH, , Concentra tiou , dos ego , On infesity Mechanism , Of dation, Presence of solvents Matter, intersing organic in hibitors. Physical Control Methods : Effect of temp Oy me obes · :deal growth temp and cardingl tempy Above max= microbio : da , · Kris twC Microber in nevisble , Below minivers microb State · microbes are tempority prevented from bot outright reverisble moniplying , not killed Auto clare Method : Steam under pressure Resort ! Steril2 ation Conditions : Bl 20 ISPs min above Normal : , , atmospheric Pressure (2 ecnosphered) Effective · acariS7 an onoscobes + endospores Pasteurization ! Method : bues exposures to heat followed by cooling Result : dis infection Essecede against Viruses , fungi , regg-re backen Vlz-a Conditous ! 1340 fo -S sees, Packe wizet is g 7. 200 for 13 Less - flash mesnod Boiling water : ac Method : boil for so win 100 , resort : disinfection Effective against : non-spore forming Patnosers Disadvantage : Items easily re-contaminated What is boiled : heat objects - resistant household -baby Products lac in nation : Method : flame open , electing heating , coils , or hote air one , Resut ? Sterilization Effective ! aganist everything Conditions : busson burner Furnances Use freezing/ drying : Freezing! Slows growth of organisms most PathogensSurvive Desiccation : * not consined a method of disinfection drying Stanzilation a on reduces of a amount Hod to support en robe growth ↳ yophilization both freeing/drying  & lonizing Radiations high energy Penetrating radiation that can remove elections , atoms creates , ronS Method : Gamma rays & X-rays Mechanisms : Cell Penetration , Creations of :ons , : Ens travel throughout and a cen collide with DNA causing breses in the DNA , Resort : Sterilization Effective egamot bacroal Pathogens of Advantages, fast Dangerous UV radiation: WV radiation Small Penerosion high - energy Nadia tros Merrods : UV Lamps Mechanisms of action : Cell penetron , interberg with DNA causing thymidine dimers that disort the DNA helix Result ! disinfection Conditions : 240nm - 280 on Disedemosses : 100 Renerating Power Ins fold Filtration : Method: liquid Passed through membrane with holes why liquid can't withstand heat Result : Sterilization What is filtered : · Gir o hear senstine ligoids  Chemical control of microorganisms ? Chemical egents of microbial control Disinfectants , contiseptics , & Sterilants Types of Chemical agents / Disinfectants & Chemical destruction of regative j Pathogens on in animate objects Antiseptics ? Chemicals appled to body surfaces ↓o destroy or inhibit vegative pathogens Sterilants Chemicals that remove /destroy all viable microbe so Characterites of chemical agents & - rapid action in low Concentration S - Solvibity in wave-/alcohol - broad-spectrum microbal action , low toxcity Penetrating - choscorrosive - - afforable and avaiable Levels of chemical decorssination ? G ermicide = microbicide = Kill pricboes Chemicals are evulated on their effective ness in killing microbes in dental/medical settings High level & ermicides Kins endospores be sterliarity , may -used to sterlize devices that are not heat seevilzable and intended to be used in Sterile enviroments Intermediate-levels Kis Suncal Spores , Viruses tubercle bacillus - used to disinfect devices that will come in contact With mucous membranes but not invasive. Low-levelsClimate vereative bacteria only Negative fungal cells , and some viruses- · used +O Clean Surfaces that touch Skin but not mucous membraness  Factor that affect sericial activites · a dequate contact time enough time for the Chemical to Penetate +o microbes and a of on the · Smooth Surface us. Porus Surface Smoots disinfected - obj ers are rapidly - Objects With Pores are harder to disinfect Biological · matter object confinested biological - an with matter Can Linden Chemical Penetration & can alter a chemical's activity · More concentrated solutions us less concentrated , Solutions diloted · Chemicals that are less more active anemical Present (more concentrated) and tend to be move I comical · Expense/ toxicity : Highly ~ concentrated Chemicals can increase toxicity and can be more & X pensive o This often vegoras a chemical to be used & ti Tul Minic i coulent - a fior, that is effective(Still gen mind Categories of chemical agents Halogens : Chlorine & iodine Disinfecants & antiseptics Chroline Mode of action · denatures enzymes - Suspends metabolic reactions · damages DNA , RNA , and fatty acids Conditions: -30 mins · less effective if exposed to light/PH Appilea tion si · drinking serage I Wase+ , was ~ fresh foods & Seas Pools · Iodine Mode of & c +: 0m ! disrupt marabolic function by interfering with Protein Structure * ppil cations Surgical · hand scrubs - topical antiseptic prep Goo 200 gety Chlorhexidine Disinfect and & antiseptic mode of & af. * o ! - de natures Proteins - damages call membrane Advantages : toxicity · more mild and lower they other antisept : 2S App... a +roms : · nebreta) wash · Controls MRS A Alcohols ? Disinfectants & antiseptic Mode of act - on ! = 30 % - destroy call membrane So-95 %- Protein coagulation - Makes Proteins thicker 100 %- dissolves well membranes & in hid IS. cell growth Applications : -removes Siein Oils Skin Cleaning ~ agent  Hydrogen Peroxide (HG0a) Disinfectant , antisepticl Stariant (vaporized) mode of action : too mean toxic oxsay tat The Call Cannot detoxify App : actions : Gase air water AC on it s , · Verstalie antiseptic Detergents & Soaps : not disinfectants , just cleaning agents · do not Kill microbes , just lift them off the Skin mean-sucaly mode of action : disrupt cell membranes · Surfacant Molecules - insert into Lord bilayer alter and permeablity Appile a from so rounde hand washing Surgical & Prop hard scrubbing