1 / 8

Where can we find bacteria?

Where can we find bacteria?. How can you find bacteria?. You can’t see it, so how do you find it? Under the right conditions, bacteria grows very fast, exponentially Some bacteria populations can double every 10 minutes

gittel
Download Presentation

Where can we find bacteria?

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Where can we find bacteria?

  2. How can you find bacteria? • You can’t see it, so how do you find it? • Under the right conditions, bacteria grows very fast, exponentially • Some bacteria populations can double every 10 minutes • Bacteria grow in colonies – a colony is a visible mass of bacterial growth on solid medium that developed from 1 or a few cells • A colony can contain millions of cells • We can find bacteria by growing it in the right conditions until it is visible to the human eye

  3. Growing/culturing bacteria • Conditions – temperature, light • Agar – source of nutrients for growth • From Malay word “agar-agar” meaning jelly • Gelatinous substance made from seaweed • Ingredient used in Japanese desserts

  4. Lab Today • We’ll look for bacteria around the classroom and school • Track your cultures • Infer good conditions for bacterial growth

  5. How to Sample Bacteria 2 Samples 3 Samples 4 Samples • Get a Petri dish • With a marker, divide it into 2, 3, or 4 equal parts

  6. How to Sample Bacteria • Write on the bottom side (side with the agar) • Write small and around the edge so you can see the bacteria growing later • Decide where you will sample and label your Petri dish accordingly

  7. How to Sample Bacteria • Get a sterile swab – don’t touch the cotton end • Swab the area to be tested • Open your Petri dish carefully and swab the cotton in the specified area on the agar • Close the Petri dish quickly • Get a new swab for each sample • When done, close the Petri dish and use scotch tape to seal the sides • Put the Petri dish upside down in a dark, warm place

  8. Photo Credits • Slide 1 (Title): http://www.norcalblogs.com/ and http://biology.clc.uc.edu/Fankhauser/Labs/Microbiology/Coliform_assays/Plates_with_Colonies/Ohio_River_0.2mL_MaC_P8011311.jpg • Slide 3: http://upload.wikimedia.org/wikipedia/commons/6/6a/Agar_Plate.jpg and masak-masak.blogspot.com/ 2007_09_01_archive.html • Slide 5: http://www3.moe.edu.sg/edumall/tl/digital_resources/biology/images/plastic_petri_dish.jpg • Slide 6: http://upload.wikimedia.org/wikipedia/commons/6/6a/Agar_Plate.jpg

More Related