CHAP 8&9

• In Vitro It refers to the events that occur outside the body.
• In Vivo It refers to the events that occur inside the body
• Nutrients They are the various chemical compounds that organisms used in order to sustain life.
• Optimum Growth Temperature The temperature at which the organisms grow best.
• Minimum Growth Temperature A temperature BELOW optimum on which organism ceases to grow
• Maximum Growth temperature A temperature ABOVE optimum which an organism dies.
• Desiccation It is the complete drying process or removal of moisture.
• Mesophiles Microbes that grow best at moderate temperatures.
• Psychrophiles Organisms that “love“ cold temperatures.
• Thermophiles Organisms that “love” high temperatures.
• Psychrotrophs This is what you call a one group of psychrophiles.
• Moisture The presence of slight to moderate amount of liquid, especially water.
• pH It refers to the hydrogen ion concentration of the solution and thus the acidity or alkalinity of a solution.
• Psychroduric Organisms Microorganisms that prefer warmer temperatures but can tolerate or endure very cold temperatures and can be preserved in the frozen state.
• Acidophiles They prefer acidic environments,
• Vibrio cholerae What is the only human pathogen that grows well above pH 8?
• Alkaliphiles They are microbes that prefer an alkaline environment.
• Osmotic Pressure A physical method that inhibits growth by limiting availability of water for metabolic activity.
• Hypertonic When the concentration of solutes in the environment outside of a cell is greater than the concentration of solutes inside the cell.
• Osmosis It is defined as the movement of a solvent (e.g.,water), through a permeable membrane, from a solution having a lower concentration of solute to a solution having a higher concentration of solute.
• Crenation It is the term for shrinkage of cells.
• Hypotonic When the concentration of the solutes outside the cell is less than the concentration of the solutes inside the cell.
• Plasmolysis It is the condition when the cell membrane and cytoplasm shrink away from the cell wall.
• Hemolysis It is what you called the bursting of cells.
• Plasmoptysis It is the escape of cytoplasm from the cell due to great pressure and the cell ruptures.
• Isotonic When the concentration of solutes outside a cell equals the concentration of solutes inside the cell.
• Halophiles Microorganisms that prefer salty environments.
• Haloduric Organisms Organisms that do not prefer to live in a salty environment but capable of surviving there.
• Piezophiles Microorganisms that thrive is an environment with extremely high atmospheric pressure.
• Fungi These cellular eukaryotic microorganisms prefer acidic environment.
• Barometric Pressure It is defined as the pressure within the atmosphere of the Earth.
• Microaerophiles Microorganisms that live in environments containing reduced concentrations of oxygen (around 5% oxygen).
• Capnophiles Microorganisms that grow best in environments rich in carbon dioxide.
• Bacterial Growth It refers to the proliferation or multiplication of bacteria.
• Generation Time It is the time it takes for one cell to become two cells by binary fission.
• Fastidious Organisms Microorganisms that are difficult to grow in the laboratory.
• Artificial/Synthetic Media The media that are used in microbiology laboratories to culture bacteria.
• Chemically Defined Medium A media in which all the ingredients are known.
• Complex Medium A media in which the exact contents are not known.
• Enriched Medium A broth or solid medium containing a rich supply of special nutrients that promotes the growth of fastidious organisms.