Aseptic Technique

Question 1

Media

Answer 1

Where microorganisms are grown and can be observed while living
-used for observation and preparation for biochemical test

Question 2

Innoculum

Answer 2

Microorganisms that are transferred intentionally in to a media

Question 3

Culture

Answer 3

-(verb) act of cultivating (growing microorganisms,
-(noun) the microorganisms themselves in the media

Question 4

Broth

Answer 4

liquid media used to culture bacteria
-the cloudiness or turbidity tells if bacteria grew, cells sediment at the bottom have to vortex it

Question 5

Agar

Answer 5

solid media used to culture bacteria found in plates or tubes
-contains all essential growth chemicals required for microbial growth
-the nutrient agar is liquid when heated but solidifies at room temp
-is a complex polysaccharide isolated from red seaweed, Is the chemical agent responsible for gel-like properties at room temp

Question 6

Colony

Answer 6

visible aggregate
-all cells in a colony are the same species and genetically identical
-cells from different colonies can be transferred to differential or selective media for tests or identification
-can also be used to create thin smear on microscope slide and stained for identification of shape, arrangement, cell wall, and cell type
-can also be transferred to and cultured on media

Question 7

Pure culture

Answer 7

-contains only one type of bacteria
-bacteria from here can be transferred from one media to another

Question 8

Aseptic Technique

Answer 8

techniques to keep outside microorganisms from contaminating your transfer culture
-done by sterilization of all equipment and media before/during the transfer of microorganisms
-have to wait 15 sec after sterilization of inoculation tools or you kill bacteria

Question 9

Sterilization of Media

Answer 9

-culture media are sterilized in an autoclave prior to being used for bacteria cultures to eradicate microbes that may have come in contact with the media

Question 10

autoclave

Answer 10

-large pressure cooker (use heat and pressure to kill microbes)
-used to sterilize liquid broth and agar by raising the boiling pt of water to 121 C and pressure at 15 psi for 15 minutes

Question 11

Intro to Aseptic technique

Answer 11

-Bacteria can be streaked or spread onto agar plates
-plates are usually placed in an incubator for 37 C or 42 C for optimal growth conditions
-the cells will rapidly divide forming colonies on the agar
-visible colonies contain hundreds of thousands of individual cells

Question 12

mixed culture

Answer 12

contains two or more types of bacteria

Question 13

Three way streak technique

Answer 13

-must be performed on mixed culture to isolate cells from each species in the culture
-generally bacteria cells are transferred from a mixed broth culture to an agar plate
-use a loop for this transfer and lightly streak on plate
-streak 1 will be the highest density of bacterial cells (sterilize loop after every streak)
-streak 2 will have a lower concentration, then repeat with another streak for even lower concentration

Question 14

Bacteria Transfer

Answer 14

-bacteria cells often transferred to fresh, uninoculated media
-bacteria in broth culture can be transferred to new broth, agar plate, or agar slant
-bacteria on agar slant can be transferred to new agar slant, agar plate, or broth
-common for broth culture to be transferred to agar plate to separate bacteria species or grow colonies

Question 15

Broth culture transfer

Answer 15

-test tubes used to store nutrient broth or culture bacteria in broth
-use an innoculating loop

Question 16

Broth culture transfer

Answer 16

-test tubes used to store nutrient broth or culture bacteria in broth
-use an inoculating loop to transfer pure bacteria to new test tube
-loop is placed over flame heated until metal is red then cooled for 15 sec
-the broth culture is vortexed
-the cap is removed (hold in hand) and the loop is placed in, immersed in new broth and heat loop again

Question 17

Agar culture transfer

Answer 17

-to transfer agar growing on a slant to another tube with agar slant use a inoculating needle
-sterilize the needle with heat remove a small amount of bacteria from the slant
-then slide the needle in a zig zag motion on the new agar slant

Question 18

Spread plate

Answer 18

-Bacteria from a broth can be evenly spread over a agar plate with a glass rod or metal triangle to grow individual colonies
-broth culture must be diluted several times because it is too concentrated before placing on plate

Question 19

Other way to heat nutrient media

Answer 19

-some media cannot be heated and maintain their chemical properties
-they are sterilized by being passed through a filter than contains microscopic pores
-microbes become stuck on filter, while media passes
-sometimes need a suction generated by vacuum because pores are so small