Lab Exam 1 Flashcards
Testing for Sugars
chemical reagent: Benedict’s solution. interacts with simple sugars (monosaccharides) and will turn green, yellow, orange or red in the
presence of various concentrations of simpler sugars .
Testing for Proteins
The presence of peptide bonds or full proteins can be tested for using
Biuret reagent. Biuret will turn light to dark purple in the presence of proteins or pink in the
presence of smaller peptide fragments.
Testing for Fats
The presence of lipids can be tested for using the Sudan IV reagent or paper.
Sudan IV dissolves more effectively in the presence of lipids or fats, forming a red color. The
red solution will float to the top, above any water-based solution. If no lipids or fats are present,
no red is found.
Testing for Starch
Chemical reagent: Iodine will stain starch
(complex carbohydrate or polysaccharide) a dark blue or black color
(View Microscope Diagram)
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- X-Y stage control
- Stage
- Object lens
- Eyepieces (ocular lens)
- Arm
- Diaphragm/ Condenser
- Rheostat
- Coarse focus
- Fine focus
- Stage clips
- Base
- Light source
- Object lens selector
Light microscopes
A) typically provide more resolution than an electron microscope.
B) work by reflecting electrons off the surface of an object being studied.
C) use light and glass lenses to magnify an image.
D) are generally not used to view bacteria.
Answer: C
Note: Light microscope has resolution limit of 0.2 μm or 200nm electron microscope can see distances down to about 2nm (1 μm=1000nm)
Total Magnification
Total magnification is calculated by multiplying the power of the objective lens and eyepiece
(ocular lens) together. Our eyepiece magnification is fixed at 10x. There are 4 object lens, 4x, 10x, 40x and 100x
1mm= ? μm = ? nm
1mm= 1000 μm = 1,000,000 nm
mm
Millimeter
μm
Micrometer
n
Nanometer
Something that is seen or felt with the senses or knowledge gained from
research or previous experience
Observation
How or why did an event occur?
Question
A tentative and testable answer to the question
Hypothesis
The recreation of a controlled event that allows the researcher to support
or reject the hypothesis
Experiment
answer whether the experiment supports or rejects the hypothesis
Conclusion
p-value for statistical significance
.05 or lower
