9 Place the loopful of inoculum into the broth and withdraw the loop
10 Again flame the lip of the tube Replace the cap
11 Removing inoculum from a plate organisms growing on an agar surface in a petri plateSterilize the inoculating loop in the flameLift the lid of the culture plate and stab the loop intothe agar away from any growth to cool the loop
12 Scrape off a small amount of the organisms and closethe lid
14 Inoculating an Agar Slant 1.Label the sterile nutrient agar slant with the source of the culture and yourinitials.2. Sterilize the loop.3. Using appropriate aseptic technique, remove a loopful of broth from the culture tube.4. Insert the loop into the sterile agar slant tube and starting at the base ofthe slant, draw the loop up the slant. Do not penetrate the agar. Sterilizethe loop.5. Incubate the slant at 37o C for hours.6. Observe the slant for growth.
18 microorganisms exist in nature as mixed populations(A mixed culture contains two or more bacterial species )However, to study microorganisms in the lab we must have them in the form of a pure culture
19 assumed to be a pure culture Streak plates allow for the growth of isolated colonies on the surface of theagar. An isolated colony is a colony that is not touching any other colonies and isassumed to be a pure culture.
20 Using a flame sterilized inoculation loop, spread (streak) the culture over a small area near the edge of the plate (1) using a continuous motion.Flame sterilize the loop and allow it to cool.Turn the plate and spread the bacteria from the end of area (1)across area(2). (You can see the streak marks of the loop in area(1.)Turn the plate in the same direction and spread the bacteria from the end of area (2)across area(3)Turn the plate in the same direction and spread the bacteria from the edge of area (3)across the rest of the plate (area4).Flame sterilize the loop before setting it down.