Bio 2400: Lab Final Exam and Already
Passed Solutions 2026-2027 Updated.
Disposal of biohazard waste in - Answer biohazard waste bucket lined with an autoclave bag
Disposal of test tubes in - Answer test tube rack in waste bucket at back of class
Disposal of glass slides in - Answer red sharps container on bench
Disposal of paper towels and gloves - Answer regular trash can that are not contaminated.
Gram positive organisms - Answer stain dark purple because thick peptidoglycan cell wall
- S. aureas
Gram negative organisms - Answer Thin layer of peptidoglycan and an outer membrane of
lipids stained by the counter stain and appear pink
-E. coli
What type of media would you use to allow growth of many bacterial species from the sampled
environment? - Answer Tryptic soy agar TSA
Lennox Broth LB
Differential Media
Where would you incubate a
soil sample - Answer Soil sample in room temperature where it grows naturally - 25C
Where would you incubate a
mouth/touch plate - Answer Mouth/Touch at 37C, close to the temperature inside the body.
Where would you incubate a sample from the frozen tundra? - Answer In cold temperature, -
4C where it grows naturally.
Proper sterilization of the inoculating loop before and after use - Answer -Sterilize the loop by
holding it in the flame until it turns red hot.
-After use, re-sterilize the loop by holding it in the flame until it turns red-hot.
, Order of aseptic technique procedure from liquid-to-plate or liquid-to-liquid. - Answer 1.
sterilize loop by holding entire wire in flame 2-3 secs.
---Hold loop in right hand, and tube in left hand.
2.remove cap of culture and sterilize mouth of tube
3. insert sterilized loop and get loop full of culture
4. reflame mouth of tube and replace cap
5. streak surface
6. reflame loop to sterilize
Microscope- Resolution: - Answer ability to distinguish two small objects apart from each
other
Microscope- Magnification: - Answer the distance of the object
calculated by multiplying the magnification of objective lens X magnification of eyepiece 10X
Microscope- Parfocal: - Answer means that when you focus a specimen under low
magnification, you can switch to high magnification and specimen will be almost in focus
function of ocular lens (eyepiece) - Answer The lens you look through. lens or group of lens
that is closest to the eye in a microscope.
function of objective lens - Answer magnification of specimen
function of stage - Answer supports the slide being observed
function of light source - Answer projects light upwards through the specimen.
function of Condenser with iris diaphragm - Answer regulates the amount of light.
function of coarse focus knob - Answer Moves the stage up and down for focusing.
function of fine adjustment knob - Answer sharpens/ clarifies the image to achieve optimal
clarity and detail
function of brightness control - Answer Can increase light intensity or reduce light.
Passed Solutions 2026-2027 Updated.
Disposal of biohazard waste in - Answer biohazard waste bucket lined with an autoclave bag
Disposal of test tubes in - Answer test tube rack in waste bucket at back of class
Disposal of glass slides in - Answer red sharps container on bench
Disposal of paper towels and gloves - Answer regular trash can that are not contaminated.
Gram positive organisms - Answer stain dark purple because thick peptidoglycan cell wall
- S. aureas
Gram negative organisms - Answer Thin layer of peptidoglycan and an outer membrane of
lipids stained by the counter stain and appear pink
-E. coli
What type of media would you use to allow growth of many bacterial species from the sampled
environment? - Answer Tryptic soy agar TSA
Lennox Broth LB
Differential Media
Where would you incubate a
soil sample - Answer Soil sample in room temperature where it grows naturally - 25C
Where would you incubate a
mouth/touch plate - Answer Mouth/Touch at 37C, close to the temperature inside the body.
Where would you incubate a sample from the frozen tundra? - Answer In cold temperature, -
4C where it grows naturally.
Proper sterilization of the inoculating loop before and after use - Answer -Sterilize the loop by
holding it in the flame until it turns red hot.
-After use, re-sterilize the loop by holding it in the flame until it turns red-hot.
, Order of aseptic technique procedure from liquid-to-plate or liquid-to-liquid. - Answer 1.
sterilize loop by holding entire wire in flame 2-3 secs.
---Hold loop in right hand, and tube in left hand.
2.remove cap of culture and sterilize mouth of tube
3. insert sterilized loop and get loop full of culture
4. reflame mouth of tube and replace cap
5. streak surface
6. reflame loop to sterilize
Microscope- Resolution: - Answer ability to distinguish two small objects apart from each
other
Microscope- Magnification: - Answer the distance of the object
calculated by multiplying the magnification of objective lens X magnification of eyepiece 10X
Microscope- Parfocal: - Answer means that when you focus a specimen under low
magnification, you can switch to high magnification and specimen will be almost in focus
function of ocular lens (eyepiece) - Answer The lens you look through. lens or group of lens
that is closest to the eye in a microscope.
function of objective lens - Answer magnification of specimen
function of stage - Answer supports the slide being observed
function of light source - Answer projects light upwards through the specimen.
function of Condenser with iris diaphragm - Answer regulates the amount of light.
function of coarse focus knob - Answer Moves the stage up and down for focusing.
function of fine adjustment knob - Answer sharpens/ clarifies the image to achieve optimal
clarity and detail
function of brightness control - Answer Can increase light intensity or reduce light.
