BISC 300 Practical | University of Delaware | Questions with 100% Verified Answers | Latest Update

BISC 300 Practical | University of Delaware | Questions with 100% Verified
Answers | Latest Update

Question: what kind of microscope is used in lab?
Answer:
brightfield

Question: What do you do when you have a culture spill?
Answer:
Warn students around you and tell your TA

Question: what is a compound microscope?
Answer:
a microscope which uses a lens close to the object being viewed to collect light (called the
objective lens) which focuses a real image of the object inside the microscope

Question: what is brightfield?
Answer:
allows direct transmission of light to specimen producing a brightly lit background

Question: what does parfocal mean?
Answer:
a lens that stays in focus when magnification/focal length is changed

Question: what is the stage of the microscope?
Answer:
platform of microscope upon which slide containing specimen to be examined is placed

Question: what is the mechanical stage of the microscope?
Answer:
can be moved in 2 dimensions by control knobs under the stage

Question: what is the condenser of the microscope?
Answer:
a series of lenses combined to func. together; purpose is to focus radiation from light source
onto specimen

,Question: what is the diaphragm of the microscope?
Answer:
below the condenser and the light source and its purpose is to control the amount of light
which reaches the condenser

Question: how many objectives are there? and what are they
Answer:
4 4x 10x 40x 100x

Question: what is the immersion objective?
Answer:
100x

Question: what is the meaning of resolution (resolution limit)?
Answer:
minimum distance bw 2 objects which still allows them to be seen as separate; not the same as
magnification

Question: what is the definition of magnification?
Answer:
the size of image, or focus, which deals with the sharpness of the image

Question: what is the numerical aperture?
Answer:
a dimensionless number that characterizes the range of angles over which the system can
accept or emit light

Question: how do you calibrate the microscope?
Answer:
with a ocular micrometer which is located inside the eyepiece and the placement of the stage
micrometer

Question: what is the conversion for the size of cells in the microscope?
Answer:
1 ocular unit = ocular unit x 10um

, Question: what is the difference between dye and stain?
Answer:
dye is the specific molecule added to the sample where stain refers to the procedure

Question: what are differential stains?
Answer:
not all the organisms will be the same color or have the same appearance (ex: gram stain)

Question: what is the simple stain?
Answer:
all organisms will have the same color (ex: flagella, capsule, spore stains)

Question: what color are gram positive cells?
Answer:
purple

Question: what color are gram negative cells?
Answer:
pink/red

Question: what is bacterial flagella used for?
Answer:
motility

Question: monotrichous flagella
Answer:
single flagellum

Question: amphitrichous flagella
Answer:
has flagella at both ends

Question: lophotrichous flagella
Answer:
tufts of flagella at one or both ends