Label the bottom of each Petri dish with experiment information. Place the Petri dishes on your work surface so they're upside down. Take a marker and label each dish with the information that you need for the experiment. [6] For example, you might write the bacteria, the date, and your initials.
How do you label and seal a petri dish?
Label and seal the Petri dishes. Once you have introduced the bacteria, you should replace the lid on the Petri dish and seal it with some parafilm or Saran wrap. Make sure to label each Petri dish with the source of the bacteria it contains, otherwise you won't be able to tell which is which.
How do you use a petri dish as a control group?
It is recommended that you keep one quadrant of the Petri dish free of bacteria samples to use as a control group. This allows you to know if the agar had been contaminated prior to the introduction of bacterial samples. Label and seal the Petri dishes.
How can I place more than one sample in a petri dish?
If you like, you can place more than one sample of bacteria in each Petri dish - all you need to do is divide the dish into quadrants (quarters) and swipe a different sample of bacteria in each of them. It is recommended that you keep one quadrant of the Petri dish free of bacteria samples to use as a control group.
How do you introduce bacteria to a petri dish?
Introduce bacteria to the Petri dishes. Once the agar solution has hardened and the Petri dishes are at room temperature, you are ready for the fun part - introducing the bacteria. There a couple of methods of doing this - through direct contact or through sample collection.
How do I label petri plates?
Label a Petri dish: Petri dishes are labelled on the bottom rather than on the lid. Write close to the edge of the bottom of the plate to preserve area to observe the plate after it has incubated. Labels usually include the organism name, type of agar, date, and the plater's name or initials.
How should a petri dish be labeled and incubated?
Proper method to label a petri plate prior to pour plating/inoculation, with initials, date, medium used, and source or dilution plated. Note the plate is labeled on the bottom edge, and should be incubated in this inverted orientation as well.
Why do you label Petri dishes on the bottom?
We label the Petri dishes at the bottom part because lid may exchange with other Petri dishes creating confusion and inverted position makes it easy to read the labeling of Petriplates.
Which 5 labels must you include when labeling your petri dish?
The label on each tube should include the name (abbreviation) of the test organism, the name of the medium, your name (abbreviation of first and last names is accepted), the date and the lab period.
Where should you label your petri plate with information about the culture?
Where should you label your Petri plate with information about the culture? All labeling should be done on the bottom portion of the agar plate. This ensures that the written information stays with your culture, even if the lid gets accidentally exchanged with another plate. Imagine you're streaking a plate.
How do you identify bacteria in a Petri dish?
Colony morphology is a method that scientists use to describe the characteristics of an individual colony of bacteria growing on agar in a Petri dish. It can be used to help to identify them. A swab from a bin spread directly onto nutrient agar. Colonies differ in their shape, size, colour and texture.
When using petri dishes Why should you always label the base of the petri dish instead of a lid?
Labeling of the lid will lead to excess condensation and then contamination of the sample because you would be required to incubate the plate with the lid facing up in order to read your labels. Labeling the lid disrupts the flow of light to the sample and will negatively impact its growth.
When you store a petri plate which side should be on the bottom Why?
All Answers (20) The plate should be face down (agar up).
Which part of a petri dish should be labeled the agar containing plastic base or the clear plastic lid Why?
Which part of a Petri dish should be labeled - the agar-containing plastic base, or the clear plastic lid? Why? Base because the lid can come off and be put on something else by accident. Also to prevent condensation for getting on the sample.
When labeling an agar plate the writing should go on the?
To label an agar plate one must always label on the agar side and not the lid of the petri dish. When labeling, it must be on the edge of the plate and not the middle because it would be hard to see your bacterium if there are labeling written in the middle.
How should a label be placed on a specimen tube?
Place the label on the blood tube, so that it is placed exactly (smooth and straight) over the embossed label on the specimen blood tube. Do not place over tube top / cap. Place the label on the specimen container “not on the lid or top” (i.e. Urines, 24 hr Urine cultures, Fluid, Blood…etc).
When labeling a sample container What information should always be included?
This label must contain two key pieces of information: the identity of the hazardous chemical(s) in the container (e.g., chemical name) and the hazards present.
How do you incubate a petri dish?
Place each petri dish inside a zip lock bag to prevent drying out and to control odors. Turn the plates upside down and put them in a warm place. The ideal temperature for incubation is 32° C or 90° F. Bacterial growth should start to become visible in about 2 -3 days.
What is the proper way of incubating culture media plates?
Ideally you should incubate the tube at 35°C for 4 hours checking every 30 minutes for clot formation. We incubate them overnight and put them in the refrigerator until the next lab period with comparable results.
How should agar plates be incubated Why?
Agar plates should be incubated in an inverted position to prevent condensation on the agar surface that could spread the inoculated organisms.
When incubating a plate what should be placed in an incubator?
T or F: When incubating a plate, it should be placed in the incubator with the lid side up. What is used in the lab to support the growth of a microbial population?
How to introduce bacteria to Petri dishes?
Introduce bacteria to the Petri dishes. Once the agar solution has hardened and the Petri dishes are at room temperature, you are ready for the fun part - introducing the bacteria. There a couple of methods of doing this - through direct contact or through sample collection.
How to get bacteria out of a Petri dish?
2. Label and seal the Petri dishes. Once you have introduced the bacteria, you should replace the lid on the Petri dish and seal it with some parafilm or Saran wrap. Make sure to label each Petri dish with the source of the bacteria it contains, otherwise you won't be able to tell which is which.
How many quadrants of a Petri dish should be kept?
It is recommended that you keep one quadrant of the Petri dish free of bacteria samples to use as a control group. This allows you to know if the agar had been contaminated prior to the introduction of bacterial samples.
Why sterilize Petri dishes?
Petri dishes must be completely sterilized before they are used for growing bacteria, otherwise, the results of the experiment could be affected.
How to measure the growth of bacteria in a Petri dish?
The results may surprise you! If you like, you can measure the daily growth of the bacteria colonies by using a felt-tip marker to trace a circle around each colony on the bottom of the Petri dish. After several days, you should have a collection of concentric rings on the bottom of each dish.
What temperature should I use for a petri dish?
The ideal temperature for growing bacteria is between 70 and 98 degrees F (20-37 degrees C). If necessary, you can place the Petri dishes in a cooler location, but the bacteria will grow a lot more slowly. Leave the bacteria to develop for 4-6 days, as this will give the cultures enough time to grow.
Can you have more than one sample of bacteria in a Petri dish?
If you like, you can place more than one sample of bacteria in each Petri dish - all you need to do is divide the dish into quadrants (quarters) and swipe a different sample of bacteria in each of them. It is recommended that you keep one quadrant of the Petri dish free of bacteria sample to use as a control group.
How to cover the bottom of a Petri dish?
Pour melted agar in to the Petri dish to cover the bottom (about a quarter) and replace the lid immediately
What is a Petri dish?
Preparation, Requirements and Procedure. A Petri dish (Petri plate) is a shallow cylindrical glass lidded dish that is typically used to culture microorgan isms (agar plates). There are glass and plastic Petri dishes, and both can be sterilized (using an autoclave) and re-used.
What to do before starting a petri dish?
Before starting, ensure that the Petri dish (dishes) is closed/has its lid on until you are ready to pour the agar in to them.
Why do you close the Petri dish before pouring agar?
For instance, closing the Petri dish before pouring the melted agar ensures that the Petri dish does not get contaminated. If stored properly, the plate is ready to be used to culture the intended microorganism. Learn more about Cell Culture, Cell Division, Cell Differentiation and Cell Staining. See the main page on Microorganisms.
How long to boil agar in a Petri dish?
Continue boiling the mixture for about one minute, and then remove from heat. Place a sterile lab thermometer in the mixture and monitor until its temperature falls to about 47 degrees (45- 50 degrees) Pour melted agar in to the Petri dish to cover the bottom (about a quarter) and replace the lid immediately.
Why is it important to use agar in a Petri dish?
Before being used for culture purposes, it is important to ensure that the Petri dish is not only clean, but also sterile. This helps prevent the contamination of the new culture. Agar is a polymer made up of various sub-units of galactose and various species of red algae.
Why is it important to take precautions when preparing agar plates?
Although it may prove easy and fun for many, it is always important to ensure that all the safety precautions are taken to avoid possible accidents and injuries. Moreover, enough care should be taken to avoid contaminating the plate, which would introduce other unwanted microorganisms in to the prepared agar plate.
Preparation, Requirements and Procedure
Common Types of Agar
- Chocolate agar
- Blood agar
- Macconkey agar
- Neomycin agar
Preparation of Petri Dish with Agar
- Before starting, ensurethat the Petri dish (dishes) is closed/has its lid on until you are ready topour the agar in to them. Requirements 1. Agar powder 2. Lab thermometer 3. Distilled water 4. Glass stir rod 5. Heat resistant hand protection 6. Boiling mixture 7. Sterile Petri dish 8. Beaker/flask
Procedure
- Measure therecommended amount of agar and distilled water in to a clean, sterile flask orbeaker
- Using heatresistant hand protection, hold the beaker/flask over a flame and stir themixture gently using a sterile stir rod while heating
- Continue boilingthe mixture for about one minute, and then remove from heat
- Measure therecommended amount of agar and distilled water in to a clean, sterile flask orbeaker
- Using heatresistant hand protection, hold the beaker/flask over a flame and stir themixture gently using a sterile stir rod while heating
- Continue boilingthe mixture for about one minute, and then remove from heat
- Place asterile lab thermometer in the mixture and monitor until its temperature fallsto about 47 degrees (45- 50 degrees)
Conclusion
- Preparation of agar plates is an easyand fun exercise for both the students and teachers/parents. Agar powder oragar preparation kit will also come with instructions/procedure, which allowsfor a much easier and fun time during the preparation process. Although it mayprove easy and fun for many, it is always important to ensure that all thesafety precautions are taken to avoid possible …