All you need are some petri dishes, agar, and sterile swabs or an inoculating needle. Agar is a gelatinous medium that provides nutrients and a stable, controlled environment for bacteria growth ( agar solution ).
Full Answer
What is the best way to set up a bacteria experiment?
I had everything else at home, so this was an easy bacteria science experiment to set up. The procedure is fairly straight forward. Label the cover of the agar plates with the surface you intend to swab. Unwrap a sterile cotton swab and pour on a little bottled water.
What do you need to make a bacterial culture?
All you need are some petri dishes, agar, and sterile swabs or an inoculating needle. Agar is a gelatinous medium that provides nutrients and a stable, controlled environment for bacteria growth.
Where can I find culturing bacteria ideas for kids?
Steve Spangler Science has a great selection of culturing bacteria ideas, hands-on experiments and bacteria science fair projects for kids! Our super-fun projects and culturing bacteria experiments will help your young scientists experience amazing and memorable bacteria growth before their eyes — in petri dish in your home or classroom!
Can I do this bacteria growth science experiment with preschoolers?
This bacteria growth science experiment is part of my Summer STEM Lab series of posts aimed at school age kids. You could absolutely do this science experiment with preschoolers but I wanted to share some of the STEM fun I am having with my 6 and 9-year-old this summer here on the blog so I created this series.
What are 2 things you need to do a bacteria experiment?
All you need are some petri dishes, agar, and sterile swabs or an inoculating needle. Agar is a gelatinous medium that provides nutrients and a stable, controlled environment for bacteria growth.
How do you feed bacteria in a Petri dish?
Pour the liquid into petri dishes — shallow plastic dishes used to grow bacteria. The agar should cover the bottom of each dish. Put each dish on a towel to dry, partially covered by its lid. The agar will start to firm in about 10 to 20 minutes.
What is in a Petri dish to grow bacteria?
Preparing the Petri Dishes. Prepare the agar. Agar is a jelly-like substance used to culture bacteria. It is made from a type of red algae, which provides an ideal growing surface for many different types of bacteria.
How do bacteria grow experiment?
0:173:06Growing Bacteria - Cool Science Experiment - YouTubeYouTubeStart of suggested clipEnd of suggested clipWe use these petri dishes. So had some petri dishes into the petri dishes we put a nutrient agar. SoMoreWe use these petri dishes. So had some petri dishes into the petri dishes we put a nutrient agar. So this just allows bacteria to grow so we pour that in there let it sit let it gel. And so forth.
How do you make nutrient agar?
0:051:33How to Make Nutrient Agar - YouTubeYouTubeStart of suggested clipEnd of suggested clipYou need to use the correct amount of powder. And hot water in order to make one liter of nutrientMoreYou need to use the correct amount of powder. And hot water in order to make one liter of nutrient agar or about 50 plates you will need 23 grams of nutrient agar.
Can you use gelatin instead of agar to grow bacteria?
Although agar is the preferred petri plate, other ingredients such as gelatin can be used when no agar is available. You can make your own substitute agar plates at home out of common kitchen ingredients. Wash your hands, your counter and all dishes you will be using thoroughly.
What can I use instead of petri dishes?
For containers, you can use foil muffin tins, clear plastic cups covered with plastic baggies, clear Tupperware with lids, or real petri dishes.
How do you make bacteria grow faster in a Petri dish?
0:061:36How To Grow Bacteria - YouTubeYouTubeStart of suggested clipEnd of suggested clipOpen the lid of a petri dish just enough to pour some liquid agar in tilt the dish until the agarMoreOpen the lid of a petri dish just enough to pour some liquid agar in tilt the dish until the agar covers the whole dish. Then let it sit for an hour so the agar. Solidifies.
How do you make agar solution?
Mix 1 level teaspoon of dehydrated agar with 100 ml (3/8 cup) of room-temperature water. Bring to a boil while stirring to ensure the agar is completely dissolved. Pour 10-12 ml of hot agar into each petri dish, just covering the bottom. Replace the dish top immediately after pouring to prevent contamination.
What does bacteria need to survive and grow?
Bacteria can live in hotter and colder temperatures than humans, but they do best in a warm, moist, protein-rich environment that is pH neutral or slightly acidic. There are exceptions, however. Some bacteria thrive in extreme heat or cold, while others can survive under highly acidic or extremely salty conditions.
How do you grow bacteria in a school lab?
Bacteria must be grown in a medium, which is a liquid or gel designed to support the growth of a bacterial culture. The media must contain everything the bacteria need to survive and can be liquid or solid. Agar is added to hot liquid media to make a gel used for culturing in plates, tubes, slants, and stabs.
How do you make a petri dish?
0:295:28The Sci Guys: Science at Home - SE2 - EP3: Homemade Petri DishYouTubeStart of suggested clipEnd of suggested clipFor the first step in preparing our medium we want to measure out all our ingredients in this caseMoreFor the first step in preparing our medium we want to measure out all our ingredients in this case we have two packages of gelatin. One teaspoon of sugar. And our package of beef bouillon.
How do you fill petri dishes with agar?
For thin agar plates, pour the agar until it has just covered the bottom of the petri plate. For longer storage of plates, particularly at room temperature, pour thicker plates - about half the volume of the petri plate. burner over the surface of the agar in the plate. The heat of the flame will pop the bubbles.
Why is bacteria not growing in Petri dish?
Your bacteria may not be growing because if wasn't placed in a warm or enriched environment.
How do you make agar gel for petri dishes?
Mix 1 level teaspoon of dehydrated agar with 100 ml (3/8 cup) of room-temperature water. Bring to a boil while stirring to ensure the agar is completely dissolved. Pour 10-12 ml of hot agar into each petri dish, just covering the bottom. Replace the dish top immediately after pouring to prevent contamination.
How do you incubate a Petri dish at home?
"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. For many microorganisms, the ideal temperature for incubation is 32°C or 90°F. Bacterial growth should start to become visible in 2-3 days."
How to make nutrient agar?
1. You’ll need a clean, microwave-safe container (a quart-sized bowl works great) to mix the agar with water and then boil it. These proportions make enough nutrient agar to prepare two Petri dishes. Stir these together well: • ½-teaspoon agar (about 1.2 grams) • ¼ cup (60 mL) of hot water.
How to grow petri dishes?
Before growing anything, some people place each Petri dish into a separate zipper-lock bag. Place the upside down dishes into a warm – about 98°F (37°C) is fine – and totally dark place to grow. In a closed box on a cable box is a great place. In a short time, you’ll be greeted by an amazing variety of bacteria, molds, and fungi. You likely see more and larger colonies over the next few days. You shouldn’t see too much growth where the disinfectants (hand sanitizers) were used. You might even see a “halo” around each location. This halo is called the “kill zone.” Measure and compare the size of the kill zone to determine the effectiveness of different antibacterial agents.
How to draw a squiggly line in a petri dish?
Lift the lid off the Petri dish and LIGHTLY draw a squiggly line in the agar with the end of the cotton swab. Roll the swab in your fingers as you draw the line. Replace the lid and label the dish with the date and the name of the item you tested.
How long to boil petri dishes in microwave?
Watch it boil (but not boil over) for 10-15 seconds before turning off the microwave. There should be no “floaties” in it.
How long does it take for agar to harden?
Loosely cover the bottom portion (set the lid ajar so excess moisture can escape) and allow the mixture to cool and harden for at least an hour. NOTE: Just like gelatin, agar needs to boil for a certain amount of time to properly gel.
How to get a good sample of a swab?
In order to get a good sample, lightly dampen the cotton swab with water. Be sure to roll the swab in your fingers so all of it touches all of the surface to be tested. You want to cover the entire cotton end of the swab with invisible bacteria.
How long does it take to dissolve agar?
Bring this mixture to a boil for three minutes to completely dissolve the agar. CAUTION: Adult supervision is required to boil water. If you are using a microwave oven to boil the mixture, be careful not to let it boil over. The mixture should be clear with no particles floating in it after boiling.
What is needed to grow bacteria?
Growing bacteria cultures requires a few things: Agar plates. Sterile cotton swabs. Bottled water. Tape. A heat source. I ordered this agar plate set because it included 10 agar plates and the sterile cotton swabs. I had everything else at home, so this was an easy bacteria science experiment to set up.
How to observe bacteria growth without label?
Rub the cotton swab on the agar plate. Place the labelled lid on top and tape it shut. Turn the sealed agar plate upside down so that the name is on the bottom. This lets you observe the bacteria growth without the label being in the way.
How to test agar plate?
The procedure is fairly straight forward. Label the cover of the agar plates with the surface you intend to swab. Unwrap a sterile cotton swab and pour on a little bottled water. Swab the surface you want to test. Rub the cotton swab on the agar plate. Place the labelled lid on top and tape it shut.
Is a refrigerator handle bad for bacteria?
For the most part, the bacteria amounts were a little unsettling, but likely are not harmful. There is no way for us to know if the bacteria grown is good bacteria or bad bacteria. We are rarely sick so I’m not too worried.
Newspaper Bacteria
All you need for this one are some cotton balls, a Petri dish full of agar (which you can find in a natural health food store) and some old newspaper to dispose of your experiment later. With your cotton in hand, take a swab of somewhere in your house - maybe the bathroom mirror, or the door handle to your home's entrance.
Osmosis with Eggs
This one might smell a bit. Fill a glass with vinegar and drop several raw, uncracked eggs inside. After two days, carefully remove the eggs and rinse off the vinegar.
Enzymes
Want to watch enzyme absorption in action? After making two rings of Jell-O according to the packet's instructions, set both into glass bowls. Now, you can cut up some pineapple and drop a slice into one of the Jell-O rings. The enzymes in the pineapple will break down the gelatin. Now you see why you're never supposed to use pineapple or kiwi.
What is the best medium for bacteria?
We can collect and grow them in specially prepared petri dishes. Blood agar or tryptic soy agar with 5% sheep's blood is an excellent medium for supplying bacteria with nutrients and an environment in which we can see them grow.
How to inoculate a petri dish?
This will transfer some of the bacteria you collected into the water. Now, inoculate a petri dish by pouring the water into the dish so the entire surface is covered. Pour out excess water. Repeat for each bacteria sample using fresh water and clean test tube each time.
How to test the effectiveness of different petri dishes?
You can test the effectiveness of different soaps by treating different petri dishes with "dirty" hands before washing and "clean" hands after washing.
What is the halo of a petri dish?
In this type of project, a petri dish is inoculated with bacteria then a paper disk (filter paper ) treated with an antiseptic agent is placed in the dish. After several days, a halo develops around the paper disk indicating a zone of no growth. Comparisons can be made between different antibacterial agents.
How long to let petri dishes sit before taking samples?
When ready to use, let petri dishes come to room temperature before taking samples (about one hour). Prepare antiseptic disks by using a hole punch to create paper disks out of a piece of filter paper or paper towel. Soak one disk in each antibacterial agent to be tested. Set aside until step 6.
Can you refrigerate petri dishes?
What to do. Prepared petri dishes should be refrigerated until used and always stored upside down (i.e media in upper dish, cover on bottom). This keeps condensation which forms in the lid from dropping onto and disrupting the bacteria growing surface.
Is gelatin a good growth medium?
In fact, this is why gelatin itself does not make a good growing medium. Some bacteria can digest gelatin, which is a protein derived from animal tissue. This destroys the growing surface in the petri plate making it unsuitable as a bacteria growth medium. CAUTION.
Why is it important to know what germs are on potatoes?
But that potato piece is important because it lets you see how many germs already existed on the potato.
How to fight germs in your hands?
The best way to fight bad germs is to wash your hands often with soap and warm water. But you need to be a good hand-washer to help protect yourself from bad germs. When you wash your hands, first wet them with warm water. Then apply soap and form a lather by rubbing your hands together.
What can a doctor do to determine what type of germs are causing someone to be sick?
Doctors can use microscopes to determine what type of germs are causing someone to be sick. This allows them to determine the best medicine to help the person get well. There are different kinds of germs, but two of the most common are bacteria (say BACK-TEER-EE-YA) and viruses (say VY-RUHS-IZ).
How to strengthen your immune system?
Eat lots of healthy foods like fruits, vegetables, and whole grains. These foods are very good for you and help strengthen your immune system, giving you a better chance to fight off diseases that could otherwise make you sick. Getting exercise and plenty of sleep also helps support your immune system.
How do viruses survive?
Viruses can only survive by living in the cells of a living thing like a person, plant, or animal. They can spread through the body and make its host (the plant, animal, or person it is living in) very sick. The flu, cold sores, and chickenpox are all caused by viruses.
What are the two systems that help fight off diseases?
Viruses – a small disease-causing agent that lives inside the cells of larger organisms, such as plants, animals, and humans. Immune System – your body’s defense system to help you fight off diseases and harmful germs.
Can germs make you sick?
Germs are very small organisms, or living things, that can cause people to get sick. They can cause you to get a stomach ache or get an infection in a cut on your hand. They are so small that you can’t see them unless you use a high-powered microscope.
What is the purpose of the Petri dish experiment?
The objective of this experiment is to learn how to grow bacteria in a controlled setting. By using simple materials from home instead of Petri dishes students will learn how to perform sterile technique. The outcome of this experiment depends largely upon their ability to keep their equipment sterile.
How to make soup with sterile tongs?
Using your sterile tongs, carefully remove one custard cup from the boiling water and set it on the tray. Using your sterile tablespoon, add two tablespoons of soup to the dish. When you set down your tablespoon or tongs, be sure to set them down across the glass to minimize contamination.
Why do surgeons use sterile techniques?
Surgeons and scientists who do tissue culture practice sterile technique because the introduction of molds or bacteria could hurt the patient or destroy the culture that the scientist is growing. Bacteria are simple one-celled organisms that reproduce by dividing into two.
How does the gut microbiome affect the immune system?
The gut microbiome contains ten times the number of bacteria cells as cells in the entire human body. It influences your immune system , emotions , and weight. There are few functions of the human body not affected by the gut microbiome.
What is the purpose of fiber in the gut?
Fiber, the ultimate prebiotic, feeds beneficial gut bacteria. Your gut bacteria break fiber down into short-chain fatty acids, which help support a healthy gut lining along with helping with the absorption of minerals such as calcium and decreasing intestinal pH. This decrease in pH helps to prevent the growth of pathogenic bacteria ( Sanz 2010 ).
What are the most resistant starches?
Fructans, found in wheat, barley, onions, banana, garlic, leeks, and artichokes, are resistant starches that promote good bacteria in the microbiome ( Gibson 2008 ). However, some people have a fructan sensitivity with symptoms similar to irritable bowel syndrome. Get tested if you think this could be you.
Does red wine help with pathogenic bacteria?
Both tannins and polyphenols found in red wine can inhibit the growth of pathogenic bacteria while stimulating the growth of beneficial bacteria. Most noteworthy, one study found that daily consumption of red wine for four weeks significantly increased the number of beneficial bacteria in the gut ( Queipo-Ortuño et al. 2012 ).
What did Yale researchers find about the effects of providing nutrients during infection?
In mouse models of disease, Yale researchers looked at the effects of providing nutrients during infection and found opposing effects depending on whether the infections were bacterial or viral. Mice with bacterial infections that were fed died, while those with viral infections who were fed lived. The paper appears September 8 in Cell.
Did mice die from being fed glucose?
The mice stopped eating, and they eventually recovered. But when the mice were force fed, they died. The researchers then broke the food down by component and found fatal reactions when the mice were given glucose, but not when they were fed proteins or fats.
Does 2-DG help with viral infections?
Giving mice the chemical 2-DG, which prevents glucose metabolism, was enough to rescue even mice who were fed glucose and allowed them to survive the infection. When the researchers did similar studies in mice with viral infections, they found the opposite effect.
Can you feed a cold and starve a fever?
A new study puts some old folk wisdom to 'feed a cold and starve a fever' to the test. In mouse models of disease, Researchers looked at the effects of providing nutrients during infection and found opposing effects depending on whether the infections were bacterial or viral.
