Explain the function of counterstain in a FISH procedure and how the most appropriate
counterstain is chosen.
What will be an ideal response
Although bound probes emit fluorescent signal, it can be relatively weak as compared with the background. A
good counterstain provides enough contrast to enhance visualization of the probe. The common counterstains,
propidium iodide (PI, reddish orange fluorescence) and diamidino-2-phenylindole (DAPI, pale blue fluorescence),
intercalate in DNA, providing a good background color for a probe's fluorescence. The counterstain should be
chosen based on how much contrast it would provide to a probe. For example, if a probe is labeled with a green
fluorochrome, PI provides a better background than DAPI.
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What is an MSDS?
a. a document that contains the reactivity and toxicity information about a material b. a document that contains the proper first aid in case of exposure to a chemical c. a document that shows where the safety material in the lab is d. all of the above e. A and B
When you take a drug, part of its effectiveness may be attributed to the placebo effect, which can be related to each of the following factors EXCEPT
A. a hidden bioactive component in the drug's formulation. B. thinking positively about the treatment's benefits. C. trust in your doctor, who prescribed the drug. D. believing you are receiving an expensive treatment.
Kevin has been suffering from ulcers and is considering seeing a doctor. Which statement is most accurate about Kevin's condition?
A. Most ulcers are the result of bacteria passed by tick bites and can be treated but not generally cured. B. His ulcers are likely caused by stress, and he should examine his lifestyle and consider adding relaxation activities. C. The ulcers most likely caused by bacteria, and so he may find relief through antibiotics. D. He should change his diet first, as most ulcers are caused by eating acidic or spicy food.
Studies using magnetic resonance imaging (MRI) machines have shown that mindfulness-based stress reduction changes the gray matter of the brain that is associated with learning and memory, regulation of emotions, and perception.
Answer the following statement true (T) or false (F)