Biology 205 Microbiology
Staph, Strep & Enteric Unknown Lab Reports
This assignment will be worth a total of 75 points toward your total course grade. These lab reports will
loosely follow a journal article format as seen in scientific journals. Be sure that you do the following:
They should be written up as three separate reports. Please staple all of the reports together.
Lab reports should be typed, written in complete sentences/ paragraph format (unless a table or
chart is requested), and follow general guidelines for college-level writing.
Be sure to include your unknown numbers in your lab report!
The body of each report should contain information as follows:
The Staphylococci: Isolation and Identification
1. Introduction:
- One to two paragraphs describing the Staphylococcus genus as a whole, medical relevance, and the goals of
this experiment.
2. Data/ Results:
- Results from all inoculations and tests.
- Include a copy of the results table on page 145, which records results of all tests for your unknown.
3. Discussion
a. In paragraph format, discuss results of identifying your unknown:
a. Were your isolates confirmed as Staphylococcus aureus? Which data support this result?
b. If your isolates were not confirmed to be S. aureus, which of the following did you determine it to be:
S. saprophyticus or S. epidermidis? Use your experimental data to support each of your findings.
c. If you were unable to perform tests or identify organisms, explain where the problems
occurred (improper streaking, inoculation, isolation, etc.)
b. In paragraph format, answer the following questions:
1. Describe the selective and differential properties of MSA for the isolation and identification of
staphylococci.
2. What are considered definitive tests for S. aureus?
3. What is a nosocomial infection and why are the staphylococci a leading cause of nosocomial
infections?
4. Why are staphylococcal infections becoming increasingly difficult to treat?
The Streptococci: Isolation and Identification
1. Introduction
- One to two paragraphs describing the Streptococcus genus, medical relevance, and the goals of this
experiment.
2. Data/ Results
- Results from all inoculations and tests.
- Include copy of Physiological Characteristics table on page 153, which records results of all tests for your
unknown.
3. Discussion
a. In paragraph format, discuss results of identifying your unknown:
a. What group/ species of streptococcal bacteria did you isolate?
b. What data led you to this conclusion?
