1. Culturing Yeast Cells on Media

2. Pre Lab Definitions: Petri Dish: A round, shallow dish used to grow bacteria. Culture: To grow living organisms in a prepared mixture of nutrients (media). Media: Substance containing nutrients needed for cell growth. Agar: Jelly to which food has been added for the growth of microbes.

3. Pre Lab Definitions: Inoculate: To introduce a microbe to an environment where it can grow. Sterile/Aseptic Technique: Laboratory procedures used in handling cultures, media and equipment that prevent contamination. Colony: A visible cluster or group of cells growing on a solid medium.

4. Pre Lab Definitions: Safety Equipment: Lab Coat, Glasses, Gloves

5. Lab- Part 1: Serial Dilution of Yeast Broth 1. Label test tubes 1, 2, 3, 4. 2. Add 9 mL of water to test tubes 1, 2, 3, 4. 4. Add 1 mL (20 drops) of yeast broth (from the shake flask) to test tube 1. (mix) 5. Pipette 1 mL of solution from test tube 1 to test tube 2. (mix) 6. Pipette 1 mL of solution from test tube 2 to test tube 3. (mix)

6. Lab- Part 1: Serial Dilution of Yeast Broth 7. Pipette 1 mL of solution from test tube 3 to test tube 4. (mix)

7. Lab Part 2- Inoculation of media with Yeast Cells 1. Label your petri dish with your group’s name and number (on the underside of the dish). 2. Swirl your disposable loop in test tube 4. 3. Use the disposable loop to spread the solution on the surface of the agar- being careful not to press too hard! 4. Place your dish in the incubator. 5. The cells will incubate or grow at 30 degrees C for 24 hours.