Classifications + Processes
Kingdoms
Kingdom Monera: simple, unicellular microorganisms composed of prokaryotic cells. Large and complex group. Nature of cell structure is the defining characteristic
—>includes all microorganisms known as bacteria: eubacteria (bacteria with typical prokaryotic cell structure), and archaebacteria (bacteria with atypical cell structure and/or function).
Nomenclature
Binomial nomenclature: method of assigning specific scientific names to individual organisms. Always a combination of the generic (genus) name and the species name
—>Generic name is always capitalized, while the species name always follows and begins with a lowercase letter. Both parts of the the name should be italicized (or underlined, if italics are not available)
Bacterial Morphology + Grouping
cocci: spherical or ball-shaped cell wall
bacilli: cylindrical or rod-shaped cell wall
spirilla: curviform, spiral-shaped, rigid, cylindrical cell wall
diplo-: bacteria that group up in pairs (diplococci, diplobacilli)
staphylo-: bacteria that group up in clusters (staphylococci)
strepto-: bacteria that group up in chains
Traits (Nutrition, preferred environments, etc)
Nutrition
photoautotrophs: use light as their energy source and carbon dioxide as their sole source of carbon
chemoheterotrophs: use chemicals as their energy source and organic compounds other than carbon dioxide as their carbon sources
Preferred Temperatures
Every microorganism has an optimum growth temperature, as well as a survival range. Temperature has a drastic impact on reaction rates and metabolic processes—> optimum growth temperature is often determined by enzymes present within the microorganism. if enzymes are operating at peak efficiency, growth can occur at a maximum rate
thermophiles: grow best at high temperatures (25-113*C), with an optimum range of 50-60*C
mesophiles: grow best at moderate temperatures (10-45*C), with an optimum range of 20-40*C
psychrophiles: grow best at low temperatures (-5-30*C), with an optimum range of 10-20*C
pH
pH, or potential of hydrogen, refers to the acidity or alkalinity of a solution; the measurement of hydrogen ion concentration. —> most organisms prefer to live in neutral or slightly alkaline environments (pH 7.0-7.4)
acidophiles: microbes that prefer environments with a pH range of 2.0 to 5.0
alkaliphiles: microbes that prefer environments with a pH greater than 8.5
Oxygen Requirements
obligate aerobes: require an atmosphere containing 20-21% oxygen
obligate anaerobes: require an atmosphere devoid of oxygen
Processes (Reproduction and such)
Bacterial Reproduction (Binary Fission)
Bacterial cell division occurs primarily through binary, or transverse, fission, in which one cell becomes two by forming a division plane across the cell
The parent cell enlarges, duplicates its chromosome, and then forms a central transverse septum across its width that divides the parent cell into two daughter cells
If conditions are favorable, binary fission is repeated at intervals by each new daughter cell in turn
With each successive round of division, the colony population doubles
Bacterial population growth is expressed by means of logarithms
Bacterial Growth
lag phase: cell growth occurs at a less-than-exponential rate; cells experience a period of intense metabolic activity in order to prepare for a growth explosion
log (exponential) phase: cells throughout population reach their maximum rates of metabolic activity and cell division; growth occurs at an exponential rate (growth rate outpaces death rate)
Classifications + Processes
Kingdoms
Kingdom Monera: simple, unicellular microorganisms composed of prokaryotic cells. Large and complex group. Nature of cell structure is the defining characteristic
—>includes all microorganisms known as bacteria: eubacteria (bacteria with typical prokaryotic cell structure), and archaebacteria (bacteria with atypical cell structure and/or function).
Nomenclature
Binomial nomenclature: method of assigning specific scientific names to individual organisms. Always a combination of the generic (genus) name and the species name
—>Generic name is always capitalized, while the species name always follows and begins with a lowercase letter. Both parts of the the name should be italicized (or underlined, if italics are not available)
Bacterial Morphology + Grouping
cocci: spherical or ball-shaped cell wall
bacilli: cylindrical or rod-shaped cell wall
spirilla: curviform, spiral-shaped, rigid, cylindrical cell wall
diplo-: bacteria that group up in pairs (diplococci, diplobacilli)
staphylo-: bacteria that group up in clusters (staphylococci)
strepto-: bacteria that group up in chains
Traits (Nutrition, preferred environments, etc)
Nutrition
photoautotrophs: use light as their energy source and carbon dioxide as their sole source of carbon
chemoheterotrophs: use chemicals as their energy source and organic compounds other than carbon dioxide as their carbon sources
Preferred Temperatures
Every microorganism has an optimum growth temperature, as well as a survival range. Temperature has a drastic impact on reaction rates and metabolic processes—> optimum growth temperature is often determined by enzymes present within the microorganism. if enzymes are operating at peak efficiency, growth can occur at a maximum rate
thermophiles: grow best at high temperatures (25-113*C), with an optimum range of 50-60*C
mesophiles: grow best at moderate temperatures (10-45*C), with an optimum range of 20-40*C
psychrophiles: grow best at low temperatures (-5-30*C), with an optimum range of 10-20*C
pH
pH, or potential of hydrogen, refers to the acidity or alkalinity of a solution; the measurement of hydrogen ion concentration. —> most organisms prefer to live in neutral or slightly alkaline environments (pH 7.0-7.4)
acidophiles: microbes that prefer environments with a pH range of 2.0 to 5.0
alkaliphiles: microbes that prefer environments with a pH greater than 8.5
Oxygen Requirements
obligate aerobes: require an atmosphere containing 20-21% oxygen
obligate anaerobes: require an atmosphere devoid of oxygen
Processes (Reproduction and such)
Bacterial Reproduction (Binary Fission)
Bacterial cell division occurs primarily through binary, or transverse, fission, in which one cell becomes two by forming a division plane across the cell
The parent cell enlarges, duplicates its chromosome, and then forms a central transverse septum across its width that divides the parent cell into two daughter cells
If conditions are favorable, binary fission is repeated at intervals by each new daughter cell in turn
With each successive round of division, the colony population doubles
Bacterial population growth is expressed by means of logarithms
Bacterial Growth
lag phase: cell growth occurs at a less-than-exponential rate; cells experience a period of intense metabolic activity in order to prepare for a growth explosion
log (exponential) phase: cells throughout population reach their maximum rates of metabolic activity and cell division; growth occurs at an exponential rate (growth rate outpaces death rate)
