In: Anatomy and Physiology
A. |
13.2 mg/ml |
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B. |
132.0 mg/ml |
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C. |
1.32 mg/ml |
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D. |
26.4 mg/ml |
What is the unit used to describe cell solutions measured in a spectrophotometer?
Cells/milliliter |
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Grams (g) |
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Optical density (OD) |
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Meters (m) |
Spectroscopy is based on the ability of compounds to specifically create certain wavelengths of light.
true or false
You are reading chlorophyll a samples in the spectrophotometer at 665 nm. Which of the following absorbance readings are considered to be inaccurate?
Abs 3.4 |
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Abs 2.7 |
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Abs 3.6 |
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Abs 2.1 |
Ideally, a standard curve should be a curved line, not a straight line.
True
False
which of the following are common uses for a spectrophotometer in a biology lab? There may be more than one correct answer.
A. |
To quantify the activity of an enzyme |
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B. |
To measure the concentration of protein in a cell sample. |
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C. |
To quantify the density of cells in a population |
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D. |
To quantify the amount of light-absorbing molecules in a sample. |
Light with a wavelength of 600 nm is used to read the absorbance of microbial cell cultures because cellular compounds (proteins, DNA, chromophores) absorb light at this wavelength and therefore do not interfere with the measurement.
True
False
The spectrophotometer output is in what units?
Absorbance (A or Abs) |
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Nanometers |
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Wavelengths |
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None of the above |
Carrots appear orange in color because they are reflecting what color of visible light?
Orange |
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Red |
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Blue |
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Violet |
Ans:- - cells/millilitres
Ans:- true
Ans:- false(it should be straight line)
Ans:-a&d(a)-to quantify the activity of the enzyme, (d)- to quantify the amount of light absorbed by the sample
Ans:- true
Ans:- wavelength
Ans:-blue/green region