MicroPara week 4 In Vitro

5 – 10% CO2 (capnophiles)

most clinical microbiology laboratories do not culture protozoa

“In glass”, meaning the study takes place in a test tube

most practical, efficient, and inexpensive method of sterilization of those inanimate objects

minimizes the possibility of contamination and protects the laboratory worker from becoming infected with the organism

have complex nutritional requirements

do not occur naturally; prepared in the laboratory

Viruses are very specific with their target, unless target is reached, they will not infect

obligate intercellular pathogens are microbes that can survive and multiply only within living cells (host cells)

most organisms will die in environments containing too little moisture

even when moisture and nutrients are lacking, many dried microorganisms remain viable but cant reproduce

not killed but metabolic activities are slowed, greatly inhibiting their growth

salt-loving (fermentation - buro)

the bacterial cell may not burst (bec of rigid cell wall) but fluid pressure within the cell increases greatly

What will happen to microorganisms in an unfavorable environment

drug or chemical that inhibits reproduction of microorganisms, but does not necessarily kill them

fastacting means the contact time should be short.

selective:only salt-tolerant (haloduric) bacteria can grow

effective means of destroying contaminated disposable materials

elimination of most or all pathogens (except bacterial spores) from nonliving objects

UV rays do not penetrate glass and building materials, are effective only in the air and on surfaces

> 100C

The following are nutritional requirements for the growth of bacteria except

If bacteria is not at its optimum temperature, (i.e., mesophile in 9 degree), it will just rest

will not grow at all on artificial culture media

most not effective; sound waves mechanically dislodge organic debris on instruments and glassware

differential: type of hemolysis (alteration or destruction of red blood cells)

enriched medium: nutrient agar plus 5% sheep red blood cells

When dry heat baking, 160°C to 165°C for 2 hours or at 170°C to 180°C for 1 hour

merely reduces the number of organism on a surface; doesnt penetrate pores & hair follicles to destroy microorganisms

All living organisms require ___ to carry out their normal metabolic processes

one in which the exact contents; chem composition is unknown

selective: inhibit the growth of Gram-negative bacteria and are thus selective for Gram-positive bacteria

use of antiseptics

optimum temp for growth: 10-20

increase in the number of organisms rather than an increase in their size (binary fission)

Level of resistance of vegetative bacteria, lipid or medium-sized viruses

large metal pressure cooker that uses steam under pressure to completely destroy all microbial life

the time taken for one cell to become two cells by binary fission

medium for culturing fungi except

use of chemical agents to inhibit the growth of pathogens, either temporarily or permanently

selective: chocolate agars containing extra nutrients plus several antimicrobial agents (inhibit all but Neisseria spp)

increase in size

used in microbiology laboratories to culture bacteria

use of liquid nitrogen

separate cells, larger viruses, bacteria, & certain other microorganisms from the liquids/gases where they are suspended

health care personnel use an antiseptic soap and scrub with a brush

faster and more effective and is less destructive form of heating

optimum temp for growth: 20-40

is one in which all the ingredients are known

Joseph Lister: dilute carbolic acid (phenol) & carbolic acid aerosol

Supports the growth of all categories of bacteria from obligate aerobes to obligate anaerobes

practiced when it is necessary to exclude all microorganisms from a particular area

added inhibitors that discourage the growth of certain organisms wo inhibiting growth of organism being sought

Most bacteria are thriving in neutral PH because neutral is the body’s normal PH

bioburden means the type and level of microbial contamination

Bactericidal agent inhibits the metabolism and reproduction of bacteria

pH 7.0 - 7.4

dehydration (drying) and freezing

5 – 10% CO2

movement of a solvent (e.g., water), through a permeable membrane; solute moves from low to high concentration

very high psi

lowest temperature that will kill all the organisms in a standardized pure culture within a specified period

may be used safely on human tissues

pH >8.5

cells are 75% - 95% water

5% O2

destruction or elimination of all microbes, including cells, spores, and viruses

refers to killing

a given virus will cause specific morphological alterations to the cells

broth or solid medium containing a rich supply of special nutrients that promotes the growth of fastidious organisms

capnophile will not die in the presence of oxygen

Lactobacillus found in yakult is an alkaliphile

pressure exerted on a cell membrane by solutions both inside and outside the cell

devoid of O2

various techniques used to eliminate and exclude pathogens (medical/surgical)

enriched medium: nutrient agar plus powdered hemoglobin

chamber where inoculated media are placed

“In life”, meaning the study takes place in a living organism

the cell does not shrink instead, the cell membrane and cytoplasm shrink

when culturing fungi — biosafety cabinet: fungal spores; petri dishes: sealed

0% O2

room air, 20 – 21% O2

acid-loving bacteria = pH 2-5

differential: mannitol fermenter (pink medium to yellow medium)

optimum temp for growth: 50-60

20% – 21% O2

sterilization of metals, glassware, some powders, oils, and waxes

Level of resistance of prions, bacterial spores, coccidia, mycobacteria

permits the differentiation of organisms that grow on the medium

a mound or pile o f bacteria containing millions of cells

What will happen to microorganisms in a favorable environment

differential: lactose (pink) vs non lactose fermenter (colorless)

devoid of microbial life

is a method of disinfecting liquids

possible to inhibit the growth of microorganisms by altering the atmosphere in which they are located

Level of resistance ofnonlipid or extremely small viruses, fungi

selective:inhibits the growth of Gram-positive bacteria and thus is selective for Gram-negative bacteria