UNKNOWN CHARACTERISTICS CHART
10/28/14
Name:
Partner:
BIOL 191 Lab Section:
Unknown Number:
Scientific Name of Unknown:
Although students work in groups, each individual must turn in an Unknown Characteristics
Report.
Objectives:
1. Students will record and organize all test results from their unknown.
2. Students will record the expected test results of possible unknowns as
indicated in the instructions.
3. Students will eliminate bacteria from contention by comparing their
unknown’s results with the expected results of the possible unknowns.
4. Students will determine the identity of their unknown.
Note: All of the characteristics or test results for every possible unknown may not be listed in
Bergey’s Manual or other sources. Manuals and texts generally only list the characteristics of
importance to that particular species. If you cannot locate a particular expected result for a
species, write “Not Listed”. However, be sure to research carefully, including online.
1
This report is organized into three sections:
I.
II.
Morphological Characteristics (p. 3)

Students must research and record the expected results for
ALL of the possible unknowns.

The Morphological Comparison Chart must be completed in
order to compare your unknown with the other possible
unknowns.
Preliminary Elimination (p. 4)
Based on the personal results of the morphological tests and
comparative research, students will eliminate certain species from
contention.
III.
Physiological Characteristics (pp. 5-6)

Students will record their unknown’s results in the
Physiological Test Comparison Chart.

After eliminating species based on the morphological
characteristics, write those remaining species in the chart
and fill in their expected physiological characteristics. The
chart is available for comparing your unknown with up to
four similar species.

Students will NOT perform every test listed (refer to the
tables in the “Physiological Characteristics” lab instructions
- p. 6).

If you do NOT perform a particular test, do NOT research
the expected results.

Use the chart to easily compare those species most similar to
your unknown.
2
I. Morphological Characteristics
Research, in Bergey’s Manual or other manuals/texts, the morphological characteristics
of ALL of the possible unknowns. Fill in the chart as follows:
Cell Shape: bacillus (rod), coccus (spherical), curved
Gram Stain: + or –
Motility: + or –
Spore formation: + or –
Cell Shape
Gram Stain
Motility
Spore formation
Your results
Bacillus
megaterium
Sporolactobacillus
inulinus
Mycobacterium
smegmatis
Staphylococcus
aureus
Staphylococcus
epidermidis
Streptococcus
sanguis
Micrococcus
luteus
Escherichia coli
Enterobacter
aerogenes
Proteus vulgaris
Pseudomonas
aeruginosa
3
II. Preliminary Elimination:
A. List all species eliminated based only on cell shape and Gram stain.
B. IN DETAIL, explain why they were eliminated. Compare the eliminated
species with your unknown.
4
III. Physiological Characteristics
Students will not perform all tests listed, only those of importance for your species.
1. Write “NA” (Not Applicable) by any tests not to be performed (refer to the Tables in
the ‘Physiological Characteristics’ student lab instructions). Do not research the
expected test results of any species for tests that you do not perform.
2. Use Bergey’s or other manuals/texts to describe the expected physiological
characteristics of those remaining possibilities, but only for the tests actually
performed on your unknown.
Therefore, you will write one of the following in each space in the Physiological Test
Comparison Chart on the following page:
1) Your test result.
2) NA.
3) An expected test result (as listed in Bergey’s or other manuals/texts).
4) Not Listed (If the test is not listed in Bergey’s or other manuals/texts/online for that
unknown).
5
TEST
YOUR
RESULTS
Compare
with…
(Write possible
unknown
species here.)
Compare
with…
(Write possible
unknown
species here.)
Compare
with…
(Write possible
unknown
species here.)
Compare
with…
(Write possible
unknown
species here.)
LactoseFermentation
Gas production
SucroseFermentation
Gas production
GlucoseFermentation
Gas production
Methyl Red
(MR in MR-VP)
Voges-Pros. (VP
in MR-VP)
Indole Test
in Tryptophane
broth
Urea Hydrolysis
in urea broth
Hemolysis
on blood agar
EMB –
Colony color
P. Isolation agarGrowth
Pigmentation
Catalase test
on agar slant
Mannitol Salt
agarGrowth
Fermentation
Coagulase
production
6