Issue 71 / September - October 2009
It's me, Peter, your Tongue!
Peter, until now I have been speaking on your behalf, telling people of your wishes, happiness, likes, and dislikes. I have been expressing the feelings in your heart and the thoughts in your mind. Now, let me speak about myself this time. Do not think that I am jealous of my fellow organs. On the contrary, we work in cooperation with each other, we help any organ that gets weak, and we do our duties as God wants us to do. Since each of us is given the perfect shape and qualities appropriate to our duties, none of us is more or less important than the others. You will not find anything useless in us. I just want you to see that I am as good as the other organs and think of all of us with gratitude.
Some people might see me as a rough piece of flesh that wiggles in the mouth. Of course I am not that simple! By looking at my color, some experienced doctors can even diagnose an illness. For example, some well-known symptoms that I show are whitening due to fever, becoming dark brown when you have typhoid, blackening because of a yeast infection, or having a smooth surface because of anemia or lack of niacin (a B-group vitamin).
If you are wondering what my primary duties are, I can say that the first is to help to produce speech, an ability which distinguishes you human beings from animals. For sure this speech production is not only mine. First of all the brain, which is the coordinator of all the organs including me, regulates all my movements in speaking. The other organs that help me form sounds to make words are your teeth, lips, palate, the vocal cords in your throat, and your lungs, which work like an air pump and vibrate those cords. As you see, so many of us work together just to produce your speech.
Other than the speech function, my second major duty is to work as an inspector to taste and process the countless fruits and delicious foods that are given by God. That is how you get an idea about an animal- or plant-based substance that you want to eat. If I did not exist, you might die because of a poisonous plant that you ate out of hunger. Many poisonous substances have a bitter taste. Indeed, I can sense their bad taste the moment I touch them and warn you to spit out the thing in your mouth immediately. When you eat sweet and delicious things, however, I make you remember and thank God, who has given them to you. However, you should be careful about my fondness for taste and control yourself since that is part of a God-given test. My Creator has made a relation between my love of taste and the evil-commanding side of your soul. He has also made me a step for your spiritual development. If you eat and drink too much, which means you are misled by your evil-commanding side and abuse my sense of taste, it will be you who lose. I do what my duty requires and get the taste of everything. But it is your job to use your will power and not to be defeated by your evil-commanding self (nafs). I will never stop you, whether you eat one piece of baklava or ten; I will get the taste of every piece. Do not ever blame me for that!
I have another function that many people are not aware of. My movement causes a negative pressure in the cavity of the mouth. Are you wondering what this negative pressure does? This pressure is needed especially for babies to nurse on their mothersâ breast easily; I help them in the sucking movement. In addition to that, as everybody knows, I have very important functions in chewing and swallowing food. I manipulate the food in your mouth; I soften and moisten it with saliva so that it can be easily swallowed. Also, during swallowing, I move the food back toward the pharynx. I have to be very careful while doing all this, since at my smallest mistake, your teeth might bite and hurt me.
Of course, I can do all this only with the help of my Creator, who has built my anatomy of delicate tissues and cells. Since He never does anything absurd or useless, He has given every organ qualities that are both esthetic and functional. My main body consists of seventeen muscles, eight of which are in pairs. They extend in all directions. Among those muscles are the lipid membrane and some salivary glands. I am the most flexible organ in your body. My many strong muscles enable me to move in lots of directions easily. Those muscles are covered by an epithelial lining which is called the mucous membrane. The small projections on my upper surface are called papillae. These papillae are of several types. They contain receptors which allow you to sense taste and the salivary glands that help me stay wet all the time. The papillae cover as far as an A-shaped line towards my back which makes up a third of my length. Here at my back, there are plenty of salivary glands and the lymphoid tissue, also known as the lingual tonsil. Many germs that enter through your mouth get trapped here. The papillae are named according to their shapes. The filiform papillae (which are long and thin) do not contain taste buds. They only provide a rough surface to move the food easily. The food is moistened by your saliva and crushed by your teeth. Then, with the help of these papillae, I help to shape the food into smaller pieces to make it easier to swallow. The fungiform papillae are mushroom-shaped and scattered among the filiform papillae. They are located at the center of my top surface and they contain taste buds. The circumvallate papillae lie along the A-shaped line which makes up the border of my back. These papillae are larger in size and smaller in number; there are around thirteen of them. Each taste bud on the fungiform papillae has 50 to 75 receptor cells which live for only seven to ten days. When cells die because of hot or acidic foods, new ones are created to make new nerves for the taste buds. Only substances that are dissolved in water can reach the taste receptors. That is why I cannot taste a dry substance that you have taken into your mouth right away; it has to be moistened and softened first. Tasting occurs in the receptor cells of taste, where some analyses are undertaken much more delicately than in a chemistry laboratory. My receptor cells change this chemical stimulus into an electrical stimulus and send it to your brain. This electrical stimulus allows the sense of taste to be perceived.
Among the many kinds of taste, there are four major groups. The taste buds for sweetness are located near my front; the taste buds for saltiness are scattered widely on my surface; the taste buds for bitterness are found at my back; and the taste buds for sourness are on my sides.
My under surface extends between my tip and the floor of your mouth. The mucous membrane that covers this surface is smooth and does not contain papillae. It is purple in color because of the many blood vessels that are inside me and nourish me. By the way, the famous saying that âthe tongue does not have a boneâ is wrong, since I do have a bone. However, this bone is not located in my front body, which is why I am very flexible and I can say whatever you command me to say. But by my muscles and ligaments I am firmly bound to a U-shaped bone (the hyoid bone) at my root. I am connected to your lower jaw by this bone.
I can have disorders, like every other organ. In fact, many disorders in me are an indication of disorders in the other organs or of a metabolic illness. For example, mouth ulcers can often be seen on me. Some types of mouth ulcer are caused by stress, lack of sleep, or lack of vitamins. Others occur as a result of absorption disorders and as a symptom of Behcetâs syndrome. Some ulcers can last for weeks and they can be very painful. You might suffer from this pain especially when you speak and eat. Diseases such as syphilis and herpes also show themselves as ulcers on me. I might even become cancerous in people who smoke or in those who eat and drink things that are too hot. I sometimes show the symptoms of some metabolic disorders like Downâs Syndrome, the blockage of lymph vessels, glycogenosis and amiloidosis. In these disorders, my muscle mass shows excessive growth due to abnormally deposited glycogen and amyloid.
Dear Peter, until now, your âspeechless organsâ have talked about themselves in their own tongue. I have always talked, but I have always talked on your behalf, expressing your thoughts and feelings. It is you who are responsible for what I have said, good or bad, since I am bound to your will power. However, today I spoke in my own tongue, and on behalf of our Creator. As is well known, I am an organ that has great potential for both evil and good. It is your duty to control me and use me well. Do not ever forget that I am not a simple mass of muscle, epithelium and nerves. Rather, I am a tool that can be used for both debasing and elevating you. From now on, when you eat an apple, do not swallow it before chewing well; wait till I get the flavor of it very well. In that way, you will have an opportunity to thank God for the food you are given. He is the One who not only gave you that apple, but also me, the organ that can taste it. This is just another amazing thing that makes your life beautiful! By thanking God, you will deepen your worship of Him.
Irfan Yilmaz is a professor of biology at Dokuz Eylul University, Izmir, Turkey.