Midterm Covering Labs 1-4 Exam with
Guaranteed Pass Solutions 2025-2026
Updated.
Microorganism - Answer A general term for living organisms that cannot be seen without a
microscope, even though some people include viruses and prions in the group.
"Ubiquity of Microorganisms" - Answer The concept that microorganisms are everywhere. It is
virtually true but not quite.
Where are microorganisms not found? - Answer Only places where we intentionally exclude
them.
Where do we intentionally not allow microorganisms to exist? - Answer Blood, cerebrospinal
fluid, pharmaceutical plants, and semi-conductor manufacturing plants, "clean rooms",
microbiology labs, and sterile growth media.
We label the bottom (agar side) for two reasons; What are they? - Answer 1. you will always
know the identity of the plate, even if the lid and the bottom become separated.
2. If condensation occurs during incubation, it will accumulate on the lid, not on the agar
surface.
In order to prevent the 3 types of contamination, microbiologists use aseptic technique. What
are they? - Answer 1. Contaminate others with microorganisms that could lead to infection.
2. Contaminate themselveswith microorganisms that could lead to infection.
3. Contaminate media and/or the microorganisms being studied in the lab.
What can disinfectants be used for and what are their limitations? - Answer They can destroy
vegetative cells and viruses but may not destroy endospores.
What are loops and needles used for? - Answer To transfer cultures. More specifically,
transferring an inoculum of bacteria.
, How long should you wait after flaming your loop/needle to transfer a culture? - Answer
Fifteen to twenty seconds
After inoculating a slant or broth, what should you do to the tube to practice Aseptic Technique
before recapping the culture tube? - Answer Flame the mouth of the tube by briefly passing it
through the flame of the Bunsen burner.
After inoculating a slant or broth, what should you do to the loop to practice Aseptic Technique?
- Answer Flame until red hot.
Biosafety Levels (BSL) - Answer Created by the Centers for Disease Control and Prevention that
take into account many characteristics of the microorganisms with specific controls for
containment, handling, and disposal of microbes at each level.
BSL-1 - Answer Microorganisms not known to cause disease in healthy adults.
BSL-2 - Answer Indigenous microorganisms that can lead to diseases of varying severity in
healthy adults.
BSL-3 - Answer Indigenous or exotic microorganisms that cause serious or potentially lethal
disease through respiratory transmission.
BSL-4 - Answer Microorganisms that are dangerous and exotic with high risk of aerosol
transmitted infections. Rarely are there treatments or vaccines for these microorganisms, and
the diseases they cause are frequently fatal.
Where and when was the first microscope invented? - Answer Middleburg, Holland. Around
1590.
What is a Brightfield microscope? - Answer The simplest form of microscopy where light is
either passed through, or reflected off, a specimen. Illumination is not altered by devices that
changethe properties of light (such as polarizers or filters).Requires the use of stains to visualize
cells.
How does a Phase contrast microscope work and what is it used for? - Answer A microscope
that converts the differences in optical density (refractive index) of cells into different shades of