MBI 240 LABORATORY SKILLS
LAB REPORTS
(Revised 1st semester 1439-40H)
Names: _______________________________________________ I.D. Nos.: ______________________________________________ Section: ______________________________________________ Group no.: _____________________________________________
Date:_______________ Group No.:________________ Section (Day):____________
2 MBI 240, Lab Report | ksu
Report No.
Topic
1 Microbiology lab organization, safety and management
2 Sterilization techniques Microbiological culture media preparation
3 Medical microbiology: Isolation of Normal Micro biota from the Human Body
4 Pure culture techniques Morphology & growth: Bacterial & Fungal Characteristics
5 Staining Techniques: Smear preparation & Gram staining
6 Staining Techniques: Endospore staining
7 Effect of physical factors on microorganisms
8 Antibiotic production
9 Effects of Chemical Agents/antibiotics on microorganisms
10 Microbial enzymatic activity
Date:_______________ Group No.:________________ Section (Day):____________
3 MBI 240, Lab Report | ksu
Report 1 Microbiology laboratory, organization and management
Make a list of instruments which are present in the laboratory you are working in.
S. No. Name English Arabic Name Uses
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2.
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Date:_______________ Group No.:________________ Section (Day):____________
4 MBI 240, Lab Report | ksu
Report 1: Answer the following questions
Q1.1 Differentiate between resolving power and magnifying power of a lens.
Q1.2 Why is immersion oil necessary when using the 100X objective? Q1.3. In Fluorescence Microscope, what kind of light is used to excite dyes and make microorganisms fluorescent?
Date:_______________ Group No.:________________ Section (Day):____________
5 MBI 240, Lab Report | ksu
Report 2
Microbiological culture media preparation & Sterilization technique 1. Write down the name, formula and purpose of the culture media your group is preparing in the lab.
Observation table
S.
No.
Name of culture
media
Formula Uses
2. Show the calculation of media preparation (100 ml)
Date:_______________ Group No.:________________ Section (Day):____________
6 MBI 240, Lab Report | ksu
Report 2: Answer the following questions
Q 2.1 What is the three main types (in terms of their physical forms) of microbiological culture media?
.
Q 2.2 Why are culture media sterilized before use?
.
Q 2.3 what are the three ways for sterilizing culture media and supplies.
Date:_______________ Group No.:________________ Section (Day):____________
7 MBI 240, Lab Report | ksu
Report 3
Isolation of normal micro biota from the human body
The microorganisms that constitute the normal microbiota of the human body are usually
harmless, although some are potential pathogens or opportunists.
These latter microorganisms may cause disease under certain circumstances.
Procedure: 1. Choose two areas of the skin that differ in terms of moisture and degree of exposure to
the outside environment.
2. Swab these areas and isolate microorganisms from each site by streaking onto nutrient
agar plates. (The swabs can be moistened with sterile water).
3. Label the plate with your name, body site, date, and type of medium.
4. Incubate the plate, inverted, at 35°C for 24 to 72 hours. Observe the agar plate after 24 to 72 hours. Select any three different isolated colonies,
describe their appearance.
Attach a picture of the result (agar plate).
Observations Colony 1 Colony 2 Colony 3
Type of Colony (Fungi or Bacteria)
Numbers of colonies with similar morphology
Colony shape
Colony surface
Colony pigmentation
Date:_______________ Group No.:________________ Section (Day):____________
8 MBI 240, Lab Report | ksu
Report 3: Answer the following questions
Q 3.1. When doing a skin culture, why is the swab first moistened with saline?
Q 3.2. Define indigenous flora of the body.
Date:_______________ Group No.:________________ Section (Day):____________
9 MBI 240, Lab Report | ksu
Report 4 Bacterial & Fungal characteristics
Observe the permanent slides of fungi. Draw a labelled diagram of each slide observed in the
class. (Take the help of the book or different websites)
Name of fungus Diagram Rhizopus
Aspergillus
Penicillium
Fusarium
Alternaria
Date:_______________ Group No.:________________ Section (Day):____________
10 MBI 240, Lab Report | ksu
Report 4: Answer the following questions
Q 4.1 Write the difference Bacteria and Fungi? Write any three differences.
Date:_______________ Group No.:________________ Section (Day):____________
11 MBI 240, Lab Report | ksu
Report 5 Staining techniques (Gram staining)
Perform the gram staining of the bacterial culture provided to you. Observe slides under 100x
(oil immersion).
Write the procedure and record the observation in the given table.
Procedure: Observation table
Name of bacteria Results Shape
Date:_______________ Group No.:________________ Section (Day):____________
12 MBI 240, Lab Report | ksu
Report 5: Answer the following questions
Q 5.1 Name the stain/chemical used for gram staining in the table given below.
Primary stain
Mordant
Decolorizer
Counter stain
Q 5.2 What part of the bacterial cell is most involved with Gram staining, and why?
Date:_______________ Group No.:________________ Section (Day):____________
13 MBI 240, Lab Report | ksu
Report 6 Endospore staining
Perform the endospore staining of the bacterial culture provided to you. Observe the slide
under microscope at 100x (oil immersion).
Write the procedure of endospore staining.
Procedure:
Attach the picture of the result. Also in the picture label an endospore, free spore
and vegetative cell.
Date:_______________ Group No.:________________ Section (Day):____________
14 MBI 240, Lab Report | ksu
Report 6: Answer the following questions
Q 6.1 After adding malachite green on the smear the slide is heated for 5 min. Why is heat necessary in order to stain endospores?
Q 6.2 Why are endospores so difficult to stain? Q 6.3. What is the function of an endospore?
Date:_______________ Group No.:________________ Section (Day):____________
15 MBI 240, Lab Report | ksu
Report 7 Effect of physical factors on microorganisms
Osmotic Pressure Procedure 1. With a marker, divide the bottom of each of the five petri plates into half. Place the name of
the bacterium to be inoculated in each section. Add your name, salt concentration, and date.
2. Streak the respective bacteria onto the five different petri plates.
3. Incubate the plates, inverted, for 48 hours at 35°C.
Observe the relative amount of growth in each section at each salt concentration.
Record this growth as – (none), +, ++, +++, and ++++ (the most).
2. Record your results in the table given below. Attach the picture of your results (agar plates with different bacterial growth).
Medium E. coli S. aureus
0% NaCl
0.5% NaCl
5% NaCl
10% NaCl
20% NaCl
Date:_______________ Group No.:________________ Section (Day):____________
16 MBI 240, Lab Report | ksu
Report 7: Answer the following questions
Q 7.1 What concentrations of NaCl are optimal for most bacteria?
Q 7.2 Why don’t bacteria lyse when placed in a hypotonic solution?
Date:_______________ Group No.:________________ Section (Day):____________
17 MBI 240, Lab Report | ksu
Report 8 Isolation of an antibiotic producer from soil
After incubation observe the plate and mark the different types of organism. Take a picture and
paste it below.
Date:_______________ Group No.:________________ Section (Day):____________
18 MBI 240, Lab Report | ksu
Report 8: Answer the following questions
Q 8.1 How many different microorganisms did you see in your soil sample?
Q 8.2 Why do organisms produce antibiotics?
Date:_______________ Group No.:________________ Section (Day):____________
19 MBI 240, Lab Report | ksu
Report 9
The effects of chemical agents/antibiotics on bacteria
Measure the zones of inhibition to the nearest mm for each of the antibiotics tested. Record
the results in the observation table.
Antiseptic Zone of inhibition (mm)
Bacteria 1 Bacteria 2
tincture of iodine
ethanol (75%)
listerine
Name of antibiotic Zone of Inhibition (mm)
Bacteria 1 Bacteria 2 Bacteria 3
Date:_______________ Group No.:________________ Section (Day):____________
20 MBI 240, Lab Report | ksu
Report 9: Answer the following questions
Q 9.1 What is the difference between an antibiotic and an antimicrobic? Q 9.2 What is the difference between microbicidal and microbiostatic?
Date:_______________ Group No.:________________ Section (Day):____________
21 MBI 240, Lab Report | ksu
Report 10
Microbial enzymatic activity
Amylase production test
Inoculate test bacteria on starch agar media and check the amylase production or hydrolysis of
starch after 48 hrs of incubation at 37oC.
Write the steps of amylase test
Procedure: Observation table
Name of bacteria Result
Date:_______________ Group No.:________________ Section (Day):____________
22 MBI 240, Lab Report | ksu
Catalase test
Carry out the catalase test on the bacterial cultures provided to you. Record the results in the
observation table.
Write the steps of catalase test.
Procedure:
Observation table
Name of bacteria Result
Date:_______________ Group No.:________________ Section (Day):____________
23 MBI 240, Lab Report | ksu
Report 10: Answer the following questions
Q 10.1 Why iodine solution is used as an indicator in amylase production test/starch hydrolysis. Q 10.2 What is the importance of catalase to certain bacteria? Q 10.3 What is the substrate of the catalase reaction?
Q 10.4. Write a balanced equation for the degradation of H2O2 in the presence of catalase.
