A laboratory specimen is a small sample of something like blood, urine, or a piece of tissue that doctors and scientists take from your body. They use these samples to see if there is anything unusual or abnormal in your body.
For example, if you are feeling sick and the doctor wants to find out what is wrong, they might ask you to give them a specimen of your urine. They will take the urine and put it in a special container and send it to a laboratory for testing.
In the laboratory, scientists will look at the urine under a microscope and test it to see if there are any bacteria or other things that might be making you sick. They can also do tests to see if you have any diseases or conditions that can be detected from a urine sample.
Overall, laboratory specimens are important because they help doctors and scientists to find out what is happening in your body and how to treat you if something is wrong. So it's ok to give them a little bit of your pee or blood or tissue, because it helps them to help you feel better soon!