Apple #108: Tonsils

As requested, I investigated tonsils. I found a lot of information that was surprising news to me. Maybe you know some of these things about tonsils already, but I didn't.

• First of all, I always thought the thing that hangs down in the middle of the throat was the tonsils. But no sir, that's the uvula. The tonsils are farther back, on either side. All of a sudden, the fact that "tonsils" is plural suddenly makes sense.
  

Image from SEER's cancer training site

• And there's more than just the two that you can see in the image. That set is called the palatine tonsils, which are at the opening of the oral cavity, or the palate. This is the set that most often gets removed.
• The second set of tonsils is called pharyngeal tonsils, which are closest to the nasal cavity. These can get enlarged and make breathing difficult and make your voice sound funny. When this happens, people say you have adenoids, although everybody has adenoids; it's just that yours can get swollen along with the tonsils nearest to your nose.
  
• The third set is called lingual tonsils, and these are on the underside of your tongue at the back of the mouth.
• Tonsils are actually made of lymphatic tissue, meaning they are one of several sets of lymph nodes scattered throughout your body. Other lymph nodes are in your neck, armpits, and groin. Lymph nodes filter the bad stuff out of lymph, a thin fluid that contains white blood cells and helps to protect you against disease.
• However, the lymph nodes in your tonsils don't seem to be especially crucial. Apparently they are sometimes not capable of handling "the multitude of viral infections that occur in children in an urban population." Speculation has it that tonsils developed a long time ago to deal with problems most children don't face anymore -- things like intestinal parasites -- or were originally built underequipped, so to speak, for today's viral threats.
• Sticking out the way they do, tonsils snag a lot of incoming bacteria and viruses. That's supposed to help your body build up an immunity to those germs, but sometimes the tonsils get overwhelmed and can't handle the germs well enough.
  
• If the tonsils are swollen and sore on a near-continual basis, or if you are having trouble breathing or sleeping, or especially if you have white, foul-smelling debris impacted in the tissue, it's time to get them taken out. If you're not sure whether your tonsils are infected, here's a picture that may help you decide.
  
• The reasons why children most often have tonsillectomies are 1) childrens' bodies need more help fighting disease than adults, who have developed more immunities 2) your tonsils keep getting bigger until puberty, and after that, they shrink.
• One last fact: another name for tonsils is amygdala, which is also the name for a part of your brain that is responsible for smell, motivation, and emotions. Both body parts are so named for the fact that they are almond (amydale) shaped (eidos).
  

Sources
US National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) training web site, Lymph Nodes - Tonsils
Texas Pediatric Surgical Associates, Tonsils and Tonsillectomy
American Academy of Otolaryngology - Head and Neck Surgery, Tonsils & Adenoids brochure, reprinted at sinuscarecenter.com
Wikipedia, Tonsil
MedicineNet.com, Definition of Amygdala
An impassioned plea against the notion that tonsils are obsolete: Giovanni J.R.C., Understanding the Functional Significance of the Once Thought Vestigial Tonsils