This is the final in a four part series from The Boy. This prompt was to explain the workings of the human body as if speaking to an Alien. The research is all his own.
While we only see the skin, nails, hair, and other features, there is much more inside than we think there is. This essay will help you learn more about the human body.
1. The circulatory system.
This is the blood, veins, and heart. You might think blood is always red. This is false. The red is from the oxygen we inhale which goes into the lungs (I’ll explain that later). Blood looks red when we bleed because of the oxygen in the air. When blood has no oxygen, it looks purple/blue, which is what we see in our veins. Those come to retrieve oxygen. Arteries, on the other hand, carry oxygenated blood.
The heart is very complex, having four chambers; two for oxygenated blood, two for oxygen-less blood, and always pumping blood. The heart is oddly shaped, not looking like your normal love heart. There is the left valve, right valve, left atrium, and right atrium. You cannot stop the heart from beating; it always pumps blood
While we mainly see our veins, we have 2 more tubes inside us that carry blood, arteries and capillaries. As I explained before, our veins carry deoxygenated blood and our veins carry oxygenated blood. What about our capillaries? Our capillaries are around our lungs, delivering oxygen to the red blood cells. They are very tiny, the shortest being as thin as a hair. Yet the cells are so flexible, they can squeeze through them! All these items are essential for our body. Without them, we could not breath, walk, talk, or see.
2. The digestive system
The digestive system includes the stomach, intestines, and esophagus.
A trip through the digestive system. A pea has entered the mouth. It gets crushed by the canines and molars. After the tongue pushes the food from the mouth, it takes a slide through a tube known as the esophagus. After about a minute, it drops down into a cave known as the stomach. It could stay in there for 1-5 hours while its nutrients are absorbed.
After it is finished with the nutrient absorbed, it goes through a test which I forgot the name of. After it passes the test, it enters the intestines. The small intestines retrieve any nutrients the stomach may have missed, and the large intestines turn it into a brown pile called poop. After about 20 hours in the digestive system, mouth to intestines, it exits us through our rectum, or butt.
3. Diseases and vaccinations
The same way our bodies defend against diseases, there are times when our immune systems fail. Here are a few well known and little known diseases. First, an explanation on vaccinations
Ever wonder how vaccine shots work? Maybe magic, maybe extra white blood cells, but no! It’s actually dead or weak cells of that disease. It sounds deadly, but when the white blood cells attack it, if you really do get that disease, the guard cells (white blood cells) will remember attacking the weak/dead cells and do the same thing!
Now I will explain some diseases.
Tuberculosis is one of the most common diseases in the world. Over 1/3 of the entire population of earth has TB. Every second, 1 person picks this up. You might have TB and not even know it! Many people have this disease and do not become sick from it.
Cancer is another common disease. This happens when a cell continually grows but does not destroy itself. Usually when a cell grows rapidly, it destroys itself. This can happen to the brain, bone, blood, and skin cells.
This disease affects the brain only. People forget things more easily like how to do a push up, walk, talk properly, and kick a ball. If not treated properly, this could lead to forgetting how to breathe! Half of all Americans know someone with Alzheimer’s.
4. Immune system
The immune system is the system that protects us from diseases. This includes some odd features. I will tell you all of the ones I know.
White blood cells prevent diseases in the blood. However, the other organs include tears, skin, and eyebrows! Tears have a chemical that kills germs. The chemical is called lysozyme, which makes germs burst open. Ear wax helps too, flowing out of your ear slowly, taking germs with it. Skin gives germs shorter life spans, making them live for only 20 minutes while on the skin. The best thing about the body is that is never gives up until the germs have stopped.
This ends my essay about the human body. New discoveries might have been made already! I hope you enjoyed this fact sheet.