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microbial physiology the study of vital life processes representative of all organisms nutrients chemical substances used in metabolism and growth macronutrients required in large amounts and is important in cell structure and metabolism macronutrient examples proteins, lipids, carbohydrates (basic cell structure) micronutrients needed in small amounts and is involved in the enzyme function and maintenance of protein structure micronutrients examples magnesium, zinc, nickel essential nutrients materials that cannot be made by an organism but necessary to sustain life and must be supplied by the diet. essential nutrient examples amino acids, fatty accids, vitamins 70% water cytoplasm 96% 6 elements CNSHOP-carbon, nitrogen, sulfur, oxygen, hydrogen, phosphorus organic nutrients contain carbon and hydrogen atoms and are the products of living things organic examples hydrocarbons- methane ; macromolecules-carbohydrates, lipids, proteins, and nucleic acid inorganic nutrients trace elements inorganic examples metals and their salts (potassium, calcium, sodium, magnesium, iron); gases (oxygen, carbon dixiode); water enviromental sources of nutrients Air 79% nitrogen 20% oxygen / Water- essential to metabolic processes/ Soil - minerals saprobes decompose dead organisms parasites utilize tissues and fluids of a living host and cause harm carbon component of all biological cells carbon functions energy sources/ structural components (cell building) heterotrophs organisms that must obtain carbon in an organic form- they feed on other organisms or the products of other organisms metabolism autotrophs organisms that use CO2 , an inorganic gas, as it carbon source energy all organisms require this to drive cellular processes metabolism extraction of energy from organic nutrients is a major role of this prokaryotes categorized by their source of carbon and source of energy photoautotrophs CO2 / sunlight/ Inorganic chemoautotrophs CO2/ simple inorganic chemical/ Inorganic Photoheterotrophs Organic/ sunlight Chemoheterotrophs Organic/ organic compounds auto =get food from carbon Carbon vital to cell structure and function transport movement of a substance across the plasma membrane passive transport does not require energy, follows concentration gradient diffusion O2 and CO2 are transported freely osmosis passive transport of water isotonic net zero hypotonic fresh water, very low solute hypertonic saltier water, high solute facilitated diffusion passive, but requires a membrane protein--protein allows channel to allow passage--polar molecules like H2O & glucose active transport carrier mediated active transport requires energy and membrane proteins- faster transport rates- has pump to cross conc. gradient enviromental factors affect the rate and amount of growth, survival depends on adaptions to changing envrioments enviromental factors examples temperature, oxygen, ph, electromagnetic radiation, barometric and osmotic pressures temperature flucuations in metabolism, morphology, transport, protein configuration 3 cardinal temperature minimum, maximum, optimum minimum lowest temp. that permits a microbes growth and metabolism maximum highest temp. that permits a microbes growth and metabolism optimum best temp promotes fastest rate of growth and metabolism phychophiles optimum temp below 15C - like the cold enviroment mesophiles otimum temps 20C to 40C - most human pathogens thermophiles optimum tem above 45C- archeans- above boiling oxidizing agent some organisms can be poisoned by oxygen--cellular damage can occur oxidizning agent examples singlet oxygen, superoxide ion, peroxide, and hydroxide radicals are toxic adaptions occurs when enzymes detoxify and nuetralize the oxidizing agent adaption examples catalase and superoxide dismutase aerobe can use gaseous oxygen in its metabolism and posseses the enzymes needed to process toxic oxygen products. obligate aerobe cannot grow without oxygen, needs oxygen for growth facultative anaerobe does not require oxygen for its metabolism and is capable of growing in the absence of it. ----has growth throughout the tube obligate anaerobe lacks the enzymes necessary for processing oxygen; will die if exposed to oxygen anaerobic lacks the metabolizing enzyme system for using gas in respiration----growth only in bottom of tube aerotolerant do not utilize oxygen gas but can grow in its presence--some growth in tube microaerophile does not grow in normal atmospheric oxygen but does need a little oxygen for metabolism---these organisms live in the soil, human body, and water,,,not directly exposed to oxygen---growth in tube just below the surface. neutral ph range 6-8 6 is more acidic, 8 is more basic fungi more tolerant of lower ph bacteria more tolerant of higher ph acidophiles like more acidic enviroment 0-2 alkalinphiles like more basic enviroment up to 10 ph osmotic pressure determines the tonicity halophiles are adapted to high level of salt- Archeans, prokaryotes baromophiles adapted to high barometric pressure symbiosis close nutritional relationships between organisms-essential and beneficial to at least one member mutualism both members must benefit mutualism examples protozoa digests,cellulose for termites, bacteria breakdown cellulose for ruminates, E.coli produces vit k in large intestine commensalism commensal benefits, they can co-exist, other member unharmed commensalism examples feed on dead cells, residual food in mouth satellitism a dependant form of commensalism. satellitism examples one provides growth factors for other, or break down toxins parastism parasite benefits; host is harmed non symbiotic organisms are free-living; relationships not required for survival synergism members cooperate and share nutrients, non essential synergism examples biofilms -cooperatives of many different organisms antagonism one member is inhibited or destroyed by another, competition for resources antibiosis production of inhibitory chemicals binary fission one cell splits into 2 asexual microbial growh reproduction generation time the time elapsed between formation of a new daughter cell and the time when it divides to form 2 new cells double population with each generation normal growth curve a graphical representation of changes in population size over time four stages normal growth curve lag phase, log or exponential phase, stationary phase, and death phase lag phase little growth-flat period of adjustment exponential growth phase period of maximum growth will continue to grow as long as cells have adequate nutrients and a favorable enviroment stationary phase rate of cell growth equals rate of cell death, caused by a depleted amount of nutrients and oxygen excretion of organic acids and pollutants death phase as limiting factors intensify cells die exponentially in their own wastes ...these cells are not supported by their enviroment measurement of bacterial growth direct total counts by counting dead cells along w/ viable cells, flow cytometer- automated, turbity