http://www.newton.dep.anl.gov/askasci/mole00/mole00564.htm Two reasons: 1. To minimize evaporation of water. 2. To minimize contamination from extraneous bacteria. In either case the water or contaminant has to diffuse up and around the inverted petri dish and cover. This diffusion is a slow process in the absence of strong convection of air.
A lot depends on what is on the plates in the first place and what conditions you are incubating under. Probably the answer you are looking for is- the growth would be so much that the individual colonies would merge together. This would make it impossible to pick a single colony for further experimentation. If the plate contains a mixed sample consider the possibility of swarming/motile bacteria taking over the entire plate. If the plate is being cultured under special conditions consider if you technique is sufficently robust to maintain them for the whole time. For example cultures at high temperaters may desicate if measures are not taken to ensure humidity.
To cultivate bacteria, you would typically streak a sample onto a nutrient agar plate in a sterile environment. The plate is then incubated at the optimal temperature for the specific bacteria species to grow. After incubation, colonies of bacteria will form, which can be studied and analyzed.
Bacteria love to grow in moist damp places - if you haven't noticed, condensation causes water droplets to form on the top of the lid and if you incubated the plate with lid on top when the water runs down the sides of the plate it can easily contaminate your culture.
If a streak plate were incubated for a week longer, there is a higher chance of overgrowth of colonies, making it difficult to differentiate individual bacterial species or isolates. The extended incubation could also lead to the drying out of the medium, affecting colony appearance and potentially inhibiting the growth of fastidious or slow-growing bacteria. Additionally, prolonged incubation may result in the accumulation of mutations over time, affecting the genetic stability of the bacterial isolates.
To accurately count colonies on an agar plate, one should use a colony counter or a grid system to track and tally individual colonies. It is important to ensure the plate is properly labeled and incubated under the correct conditions to allow colonies to grow distinctively. Counting should be done systematically and consistently to avoid errors.
Advantages: 1. Counts only living cells 2. Standardized test - used worldwide Disadvantages: 1. 1-2 days of incubation 2. Melted, heated agar 3. Osmotic shock
A control plate is used for testing a known result on controlled bacterial strains in microbiology. They are typically incubated.
The streak lines would show a lot of colonies.
to prevent condenstion of the gel
Magic.
The Peerless PLP-UNLP is a fixed position plate and does not allow for rotation of the screen.
A lot depends on what is on the plates in the first place and what conditions you are incubating under. Probably the answer you are looking for is- the growth would be so much that the individual colonies would merge together. This would make it impossible to pick a single colony for further experimentation. If the plate contains a mixed sample consider the possibility of swarming/motile bacteria taking over the entire plate. If the plate is being cultured under special conditions consider if you technique is sufficently robust to maintain them for the whole time. For example cultures at high temperaters may desicate if measures are not taken to ensure humidity.
To cultivate bacteria, you would typically streak a sample onto a nutrient agar plate in a sterile environment. The plate is then incubated at the optimal temperature for the specific bacteria species to grow. After incubation, colonies of bacteria will form, which can be studied and analyzed.
Mexico One Plate at a Time - 2003 Pizza of the Three Cultures 2-2 was released on: USA: 2004
Bacteria love to grow in moist damp places - if you haven't noticed, condensation causes water droplets to form on the top of the lid and if you incubated the plate with lid on top when the water runs down the sides of the plate it can easily contaminate your culture.
Whether it's staining, cultures or magnification we all go by the motto "less is more". You start with the lower power magnifications to position the plate and increase power until you get a clear view.
The small bread plate goes at the 10-11 O'clock (forward and to the left) position to the dinner plate.