Name:



Name: _________________________“Excuse me, Doctor, don’t I need that?”Read the essay below, and answer the questions that follow.It is not uncommon for school-aged children to get six or more upper respiratory infections (such as the common cold or strep throat) every year. Sometimes, these infections can result in a condition called tonsillitis, or an infection of the tonsils. The tonsils are two small clumps of tissue in the back of your throat that help fight off infections, but when these get infected themselves, doctors can choose to remove the tonsils to help you heal. This surgery is called a tonsillectomy, and it is the most common surgery performed in children. How is it that an organ can be removed and we can simply move on with life as if nothing has happened?As it turns out, our tonsils are not the only organs that get infected and harmlessly removed on a regular basis. The appendix is a small organ, approximately 4 inches long, which can be found hanging off of our intestines in the lower right part of our abdomen. Appendicitis is an infection of the appendix that often turns deadly, so the appendix must be quickly removed if such an infection takes place. So what does the appendix do? Well, no one really knows. Doctors and scientists have researched this mysterious piece of flesh for years, and it apparently does nothing at all. Scientists call this wonder of nature a vestigial trait, which is a structure that probably once had an important function in our ancestor but no longer serves any useful purpose.The human body is full of useless structures – vestigial traits. We humans have a “tail bone”, but we don’t have a tail to match it – or do we? Well, certainly not now, but when you were a fetus, you were sporting quite the tail-like structure from 3 to 6 weeks old. Almost all of it disappeared, but we still have an extra bone in our spine, called the coccyx or “tail bone”.What about “wisdom teeth”? This extra set of molars often pops up around the ages of 17 to 25, and very rarely is there actually room in the mouth for them. This results in a condition called impaction, where the new set of teeth grow in sideways, get stuck underneath other teeth and gums, and have to be surgically removed. Why grow another set of molars when there is no room for them? No one really knows for sure, but scientists think that wisdom teeth are yet another vestigial trait left over from our ancestors. These are just a few of the many useless gems in the human body. Despite the evolutionary mistakes, there are many amazing features of the human body that do amazing things for us. When you are finished answering the follow-up questions, flip over the sheet to take a look inside the human body.What do you think the suffix “-itis” means? (look at tonsillitis and appendicitis) ______________________What is a vestigial trait? ___________________________________________________________________Give two examples of vestigial traits _________________________________________________________Are there any other traits on the human body that you think are vestigial? Which ones? _____________________________________________________________________________________________________ ................
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