Microbiology Lab Practical 1
(TAMUCC) Questions and Answers
100% Pass
How is total magnification calculated? - ✔✔Multiply the ocular lens (10x) by the
objective lens
10x*10=100x
40x*10=400x
100x*10=1000x
OCULAR TIME OBJECTIVE
what is the function of immersion oil when using the oil immersion objective? - ✔✔the
immersion oil allows for magnification and increases the contrast of the specimen
What is meant by the term parfocal? - ✔✔Once the lens is focused on a particular area it
will remain focused on the particular area regardless of changing the objective
Katelyn Whitman, All Rights Reserved © 2025 1
, why aren't the magnifications of both lenses of binocular microscope used to calculate
total magnification? - ✔✔Because the image only goes through one ocular to reach both
eyes
Why is the 10x placed in position when the microscope is stored or carried? - ✔✔The
low-power objective is farther away from the stage than the other objectives so the lens
is less likely to get scrapped during handling.
What is an aseptic technique? What is its importance? Why do you always have to do it
in the microbiology lab? - ✔✔-Microbiologists use aseptic technique for a variety of
procedures such as transferring cultures, inoculating media, isolation of pure cultures,
and for performing microbiological tests.
-Proper aseptic technique prevents contamination of cultures from foreign bacteria
inherent in the environment.
what are some aseptic techniques used when transfering cultures from plate to broth
tube and agar slant? - ✔✔1. Prepare your desktop by swabbing down its surface with a
disinfectant.
2. Wash your hands
3. With a marking pen, label a tube of sterile nutrient broth with name, date and
specimen
Katelyn Whitman, All Rights Reserved © 2025 2
(TAMUCC) Questions and Answers
100% Pass
How is total magnification calculated? - ✔✔Multiply the ocular lens (10x) by the
objective lens
10x*10=100x
40x*10=400x
100x*10=1000x
OCULAR TIME OBJECTIVE
what is the function of immersion oil when using the oil immersion objective? - ✔✔the
immersion oil allows for magnification and increases the contrast of the specimen
What is meant by the term parfocal? - ✔✔Once the lens is focused on a particular area it
will remain focused on the particular area regardless of changing the objective
Katelyn Whitman, All Rights Reserved © 2025 1
, why aren't the magnifications of both lenses of binocular microscope used to calculate
total magnification? - ✔✔Because the image only goes through one ocular to reach both
eyes
Why is the 10x placed in position when the microscope is stored or carried? - ✔✔The
low-power objective is farther away from the stage than the other objectives so the lens
is less likely to get scrapped during handling.
What is an aseptic technique? What is its importance? Why do you always have to do it
in the microbiology lab? - ✔✔-Microbiologists use aseptic technique for a variety of
procedures such as transferring cultures, inoculating media, isolation of pure cultures,
and for performing microbiological tests.
-Proper aseptic technique prevents contamination of cultures from foreign bacteria
inherent in the environment.
what are some aseptic techniques used when transfering cultures from plate to broth
tube and agar slant? - ✔✔1. Prepare your desktop by swabbing down its surface with a
disinfectant.
2. Wash your hands
3. With a marking pen, label a tube of sterile nutrient broth with name, date and
specimen
Katelyn Whitman, All Rights Reserved © 2025 2
