I love homeschooling, and online learning. I want to get away from the textbook and get hands-on. This is one of my favorites — it’s a lab and lesson on how we found out about penicillin. I’ve got a list of materials and where you can can get them. Bread is easy to find, and letting it get moldy — well I hope you know how to do that. But there’s some tips in the video. Get your kids a blank lab book for taking notes and drawing pictures. But first, watch this video produced by MIT for grades K-12, and you will see what to do and how much fun you can have with this science lesson. Then get the materials and watch the video again with your kids.
Goal: To understand how penicillin was first discovered and how it kills bacteria. Other uses of penicillium are noted as well.
These are the items you will need to do this science lab:
- Petri Dishes with Agar (see notes on sources for these at the bottom)
- Wooden popscicle sticks
- Bread and a plastic bag or jar with water (or let it mold naturally in the bag)
- Lab book for taking notes and drawing pictures of the experiment.
Watch this video which demonstrates the experiment you will be doing on how bread mold (penicillin) kills bacteria.
Teaching Ideas to share with your kids:
The bread mold, Penicillium consists of a network of filaments (hyphae) known as a mycelium (white). It has numerous reproductive spores which are the green/grey areas. The mold is penetrating the bread, using the moisture and nutrients to grow. Share this picture with your kids and have them draw it in their books. Notice that it is very blue-green on the bread.
This is a magnified view of penicillium that is used to make the antibiotic penicillin.
Penicillium
penicillium conidia
Other Uses of Penicillium
Penicillium molds are used to make cheese:
Penicillium candida used in making Brie cheese and Camembert cheese (its in the rind)
Penicillium roqueforti used in making Roquefort and Danish Blue cheese
Sources for materials:
- Petri Dishes and Agar: Fischer Scientific
- Home Training Tools: Petri Dishes and Agar
- Wooden Craft Sticks: Amazon
Oh, Deila… now you’re in my favorite place… microbiology! That and chemistry were my two favorite college classes! Very cool! I wish I had known these things when my kids were in home school, but I never took micro until I was in my 50s… and my kids were fully grown. I had more fun in micro than you can imagine. My microbiology teacher became a dear friend of mine. I remember when we were experimenting on our “unknowns”, I had done many tests on my unknown and was convinced I had E. coli. The teacher said she wanted me to do one more experiment before turning in my results, so I thought, “I’ll do a culture on EMB medium and that will clinch it!” So I inoculated the EMB with my “unknown”, but I didn’t do it the NORMAL way — no, I inoculated it so that when it grew into its shiny metallic green self on the EMB, it would form the word “HI”! So I took it to the teacher after its weekend of growth and said, “Mrs. Denis-Arrue! Look, my bacteria is far more intelligent than we suspected!” There it was — metallic green “HI”… we couldn’t stop laughing! So much fun! Thanks for sharing this. Guess I’ll have to wait for some grandkids to do this. Do you ever do any of this stuff with your grandchildren, Deila?