what is the sample in a research study
Ideally, this is a population at risk. The study population is the population from which sample is to be drawn. Commonly, the population is found to be very large and in any research study, studying all population is often impractical or impossible. Therefore, sample unit gives researchers a manageable and representative subset of population.
A NO IT does not mean you are allergic to them. If that was the case then you would have itching and swelling in other parts of your body, such as around your mouth. It just means that your immune system reacts to the chemicals in the bites slightly more than average.