BIOD 171 LAB 4 NOTEBOOK SUMMER 2025 Portage learning

BIOD 171 LAB 4 NOTE

Title: GE04 Growth Media

Objective: To understand the types and uses of growth media for
isolating and identifying unknown bacterial samples.

Procedure:

4-phase dilution streaking: clonal isolation

1. Using sterile loop spread culture in area #1

2. Using the new sterile loop, drag through the end of area #1
once

3. Using the new sterile loop, drag through the end of area #2
once

4. Using a new sterile loop, drag through the end of area #3 once.

Use a back-and-forth pattern to dilute the culture in each zone.

Invert the plate and incubate overnight at 37 C



(non-selective agar).

Quadrant growth: rapid test for multiple isolates

1. Using a sterile loop, spread unknown culture A in area #1

2. Using a NEW sterile loop, spread unknown culture B in area #2

3. Using a NEW sterile loop, spread unknown culture C in area #3

4. Using a NEW sterile loop, spread unknown culture D in area #4