______________ can prevent some bacterial cells?
7th grade science please help me.
To answer your question, I assume you are asking about a substance or method that can prevent or inhibit the growth of bacterial cells. One such substance is an antibiotic. Antibiotics are drugs or natural substances that can kill or inhibit the growth of bacteria.
To find the answer to your question, you can conduct a simple experiment to test the effectiveness of different substances on bacterial growth. Here's a step-by-step guide:
1. Gather your materials: You will need agar plates (a petri dish filled with a gel-like substance that bacteria can grow on), a bacterial culture (such as Escherichia coli, commonly known as E. coli), and different substances to test (such as various antibiotics or household items like soap, vinegar, or disinfectant).
2. Sterilize your workspace: Make sure to clean your work area and sterilize any necessary equipment to prevent contamination.
3. Prepare your agar plates: Label each plate with the substance you will be testing. Melt the agar and pour it into the petri dishes. Let the agar solidify.
4. Inoculate your plates: Using a sterile inoculating loop or cotton swab, carefully streak the bacteria (E. coli) across the agar surface of each plate.
5. Apply the substances: Using a sterile dropper or swab, apply a small amount of each substance (antibiotics or household items) to their respective plates. Leave one plate as a control (without any substance).
6. Incubate the plates: Cover the dishes and put them in an incubator set to the appropriate temperature for bacterial growth (usually around 37°C or 98.6°F). If you don't have an incubator, you can store the plates in a warm place like an airing cupboard.
7. Observe and measure the results: After 24-48 hours, check the plates for bacterial growth. Measure the size of the bacterial colonies, note any areas where growth has been inhibited or killed, and compare them to the control plate.
8. Analyze the data: By comparing the growth on different plates, you can determine which substances effectively inhibit bacterial growth. This will help you identify what can prevent bacterial cells.
Remember, this is just one way to test the effectiveness of different substances on bacterial growth. It's important to consult with your teacher or a scientific mentor to ensure proper safety precautions and methodology during your experiment.