Believe it or not, the process of completing a DNA test is not very difficult. First of all, human cells must be collected. The cells can be collected from a person's cheek using a swab. The next step is to send this cell sample to a laboratory, where scientists extract the DNA from the swab and create many samples from it. Then the samples are put into a gel mixture, and are subjected to an electric current. A DNA probe can then be used, which attaches itself to the sample. Each person produces a unique location of DNA attachment, and this is how the identification works. Ultimately, scientists develop the film of this unique DNA strand. This type of DNA test becomes more reliable as more probes are used to test the strand. DNA testing has become very popular, so it is now available on the Internet. Ordinary people can now order in-home DNA tests and get their results in just a few days.
Answer the following questions:
1) What is the topic sentence of this paragraph?
2) How many steps make up the process of DNA testing? Which are they?
3) Write two transitional expressions that show a time relationship.
4) What surprising information is given in the last two sentences of the paragraph?
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