MICROBIOLOGY LAB EXERCISES
15 WEEK SEMESTER
Lab Session #
Topic and Page #
Supplies/ Cultures
1
Welcome to Lab Safety
pg, ix – xi. View safety
video
Safety Video and VCR
or LCD
2
Brightfield Microscopy
- pg. 3
3
Protozoans, algae, and
Cyanobacteria - pg. 33
Total supplies &
Culture for (1) one
section (24) students
Some instructors might
require prepared Blood
slides. Slides of letter e.
Instructors are to
ensure that Students
are to record results in
form of drawings, etc
and answer all
questions at the end of
each lab exercise
during the entire
semester.
Human Blood slides,
slides with 3 bacteria
morphologies; Prepared
slides of Amoeba,
Paramecium,
Saccharomyces-yeast,
Euglena, spirogyra
Commerical Protists
(Euglena, Paramecium,
diatoms, etc.)
Lots of covers slips
1 NA plates, 1 Blood
agar plates per 3-4
students, 2 NB tubes
per student, sterile
cotton pads
Students will ONLY
use Exe. 37 as a
comparison for colony
growth and appearance
Wet mount techniques
4
Ubiquity of Bacteria pg. 47
NA plates, Blood agar
plates, NB tubes, sterile
cotton swabs/pads
5
Results from previous
lab. Review Exe 37
pg. 245
Review Exe 37
6
Aseptic Technique - pg.
63
8 NB of E.coli
8 NA slant of
M. smegmatis
8 NA plate with
colonies (E.coli,
M.luteus, S.
marcescens)
Lab Aide should talk to
the instructor about the
number of media tubes
and plates required by
each student (24 each)
7
Record results from
previous lab:
NA plate with colonies
(E.coli, M. smegmatis,
S. marcescens, M.
luteus) form previous
lab
8
Pure Culture techniques
- pg. 73
Streak and Pour Plate
Techniques
60 NA Deeps
125 sterile petri plates
sterile
8 NB mixed culture and
8 NA plates of mixed
cultures of
S.marcescens, E.coli,
M.luteus. Hot plates
9
Record results from
previous lab. Continue
with subculturing
techniques
48 NA slants, three
slant tubes per group of
3 students
10
Smear preparation and
simple staining - pg.87
– 91
Clean glass slides,
USE CULTURES
FROM PREVIOUS
LAB
11
Negative Staining –
pg. 93
USE CULTURES
FROM PREVIOUS
LAB
NA plate with colonies
(E.coli, M. smegmatis,
S. marcescens, M.
luteus) form previous
lab
It is suggested that a
negative control. Such
as S. aureus be
provided also.
12
Gram Stain - pg.101
8 NA plates of
B.megaterium,
8 NA plates- S. aureus.
Gram stain reagents
(make sure iodine is the
color of tea). Cultures
should be no older than
24 hours.
For a Monday lab, it is
suggested that cultures
be set up on Friday and
incubated at room
temperature. Instructors
should notify Lad Aid
if they require
additional/ different
cultures.
8 NB - P.aeruginosa,
8 NB- M.smegmatis.
Gram stain reagents
(make sure iodine is the
color of tea). Cultures
should be no older than
24 hours.
For a Monday lab, it is
suggested that cultures
be set up on Friday and
incubated at room
temperature. Instructors
should notify Lad Aid
if they require
additional/ different
cultures.
Day 1, use cultures
prepared on NA slants
13
Gram Stain - pg.101
Day 2, use cultures
prepared on NA slants
Students should work
in groups of 2, each
will get 5 20 ml deeps
and 5 NA plate
14
15
Spore Stain - pg. 105
Acid Fast Stain - pg.
103
8 NA slants or plates
(24 -36 hours old) of
B.megaterium,
8 NA plates of
S.aureus
hot plate, malachite
green, safranin
8 NA slants or plates of
M.smegmatis (48 hours
cultures),
8 NB of S.aureus,
hot plate, carbolfuchsin,
acid-alcohol, methylene
blue
It is suggested that a
negative control. Such
as S. aureus be
provided also.
16
Motility Determination
- pg. 107
8 NB of P.vulgaris
8 NB of Micrococcus
luteus
(cultures should be
young)
2 tubes of SIM per 4
students, depression
slides, clean slides,
cover slip, Vaseline.
17
The Fungi - pg. 53
Prepared slides of
S.cerevisiae*
Broth cultures of S.
cerevisiae, methylene
blue stain, clean
slides/cover slips
Students will also look
at prepared mold slides
that contain all three:
Penicillium,
Aspergillus, Rhizopus
18
Capsular Staining
capsular staining can
also be done with
Klebsialla pneumoniae
The cultures for these
procedures are listed in
the manual.
19
LAB Midterm Exam
20
The Standard Plate
Count method of
estimating bacteria
population- pg. 139
8 NB E.coli,
5 - 20 ml NA deeps per
2 students, 5 sterile
Petri plates per 2
students,
4 - 99 ml sterile water
blanks per 2 students,
6 - 1.1 ml pipettes per
student, biohazard bags,
pipette pumps( 1 per
group of 3 or 4)
Three 99ml sterile
water blanks, 4 sterile
empty petri plates and 4
sterile pipettes per
group of 4 or 3
students. The Lab Aide
should talk to instructor
about the logistics of
this exercise. How
many blanks and plates
per group?
21
Record results from
previous lab.
Instructor should go
over several
quantitative plate count
calculation problems
with students.
22
Differential Plates
Antimicrobic
Sensitivity Testing –
The Lab Aide should
prepare various media;
i.e.; Na; EMB, MSA,
MAC, CITRATE
ACID, SIM etc…..
The Lab Aide should
talk to instructor about
the logistics of this
exercise.
24 Plate MuellerHinton II agar
8 NB of each - S.
aureus, E.coli, P.
vulgaris, P. aeruginosa
Cartridge of disk and
disk dispenser
Antibiotic discs list:
penicillin,
streptomycin,
erythromycin,
kanamycin, ampicillin,
tetracycline,
All students are to carry
out the unknown
identification exercise
and submit a report on
their investigation for
grading
The Lab Aides should
talk to each instructor
about the logistics of
this exercise.
Each student/group
will be given TWO
organisms in their
unknown cultures.
pg. 215
23
Continue Ex. 33
(Results observation
and interpretation)
24
Start Unknown- pg.263
25
Continue Unknown
26
Continue Unknown
27
Continue Unknown
28
Final Exam
(Clean up)
29
(Clean up)
30
*OPTIONAL LAB
COULD NOT FIT THIS
INTO PRESENT SCHEDULE
Cultivation of
Anaerobes
Lab exercise 19 in lab
book
We could sub this lab in place
of one the above labs, let’s
discuss it ASAP.
Observe and record
results from previous
lab.
6 Fluid thioglycollate
broth medium (FTM)
tubes with resazurin
dye per group of 3
students or per table.
Gas Pack jar set- 1 per
class
6 NA plates per group
of 3 students or per
table.
One 24 hr broth
cultures of the
following per group: M.
smegamtis, S.aureus,
M.luteus, E.coli, P.
aeruginosa, C. rubrum