Exploring the scientific process of food digestion (from the mouth to the anus).

The fact that we do not have control over time is one important reason why we should never joke with it, these were the words I muttered to myself after I opened my hive account this week and realized it has been two long years already. It has been a long unproductive year for my company and after trying so hard to maintain stability some of us had to be relieved of our duties, it seemed like a very bad time for this to happen but, I knew I could not sit and cry for too long, I had to pick up myself and get going before things would get worse. While applying to remote roles online with the hope that I will get another job before the year runs out or possibly by next year, I remember I use to run an hive account before I got so busy with work.

I was excited to find my passwords still carefully placed where I had left them, so I started looking around again with the hope to reconnect and hopefully, I am able to find my path again. I opened the @stemsocial community where I got so carried away with reading topics on human health, illnesses amongst other things, I said to myself, this is a good place to be and I hope I am received with warmth as I would really love to be a part of these smart humans.

Enough of boring you with the story of my life, I'll like to share with you, a very interesting and highly beneficial topic and since I will be positing on the steemsocial community, it definitely has to be a science based post just like I have observed other writers here do as well. I really hope you enjoy reading.

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The Operational Process of the Digestive System.

It is normal for us to conclude that the process of digestion simply happens in the mouth and then excretion happens in the anus, but there is a lot more complications happening in between that meets human physical eye. The food we eat, fulfills the purpose of fueling our bodies for energy, growth and repair, but it isn't just that simple, there is a lot of transactional occurrences that goes on in between.

Digestion is extremely important, this is because the body needs a lot of nutrient from the food and the drinks that it consumes in order for it to work appropriately as well as remain healthy. Nutrients in form of carbohydrates, vitamins, proteins, fats, minerals and water are taken into the body in order to sustain health. The digestive system then proceeds to break down the consumed nutrients into smaller parts, the sub-divided parts are enough for the body to absorb energy and utilize it for energy, growth and the repair of cell. Nerves and hormones help in controlling the digestive process.

Food is broken down into smaller parts during the process of digestion through chewing, squeezing and mixing.
The movement of food begins in the mouth, food moves through the GI tract after eating. When food is being swallowed, the tongue pushes the food into the throat, then a small flap of tissue, known as the epiglottis, would fold over the windpipe, this is to prevent choking during the swallowing process and the food passes gently into the esophagus.

Food passing through the esophagus is an automatic process, the moment swallowing begins, the brain signals the muscles of the esophagus and peristalsis begins. When food gets to the end of the esophagus, the lower esophageal sphincter, in a ringlike form, relaxes and gives room for food to have easy passage into the stomach. The sphincter often remains closed in order to prevent what is in your stomach from flowing back into the esophagus. The food then moves into the stomach, upon entering the stomach, the muscle in the small intestine mixes food up with digestive juices available in the pancreas, liver and the intestine and push them further for digestion. The walls of the small intestine absorbs water and the available digested nutrients into the bloodstream, while the waste products of the digestive process are channeled into the large intestine.

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The muscles of the small intestine mixes up food with the available digestive juices from the pancreas, the liver and the intestine, it then push the created mixture for further digestion. The existing walls of the small intestine, absorbs water and other digested nutrients into the bloodstream, as this process moves forward, waste products from the digestive tract gets moved into the large intestine.

Large intestine, absorbs water and converts the waste from liquid form into stool, peristalsis helps with moving the stool into the rectum.
We finally have the rectum, which is at the end of the large intestine, the rectum stores stool until it is able to push the stool out of the anus during a bowel movement.

The journey for the digested food is in the small intestine, this is where the absorption of major nutrients happen, the circulatory system then moves them to the other parts of the body where they are either stored or used. Special cells help with the absorption of nutrients across the intestinal lining into the bloodstream, the blood moves simple sugars, glycerol, amino acids and some vitamins and salt into the liver. The liver proceeds to store, process and ensure the delivery of nutrient to the remaining parts of the body when they are required.
The body also makes good use of fatty acids, sugars and glycerol for the building of substances required for growth, energy as well as the repair of cells.

Digestion is controlled in the body, through the capable function of the hormones and the nerves who work together to ensure the control of the digestive process. Signals flow conveniently within the GI tract and moves back and forth from the GI tract into the brain.

The hormones are made and released through cells lining the stomach and the small intestine, these hormones control the operational process of the small intestine, they send information on the appropriate time for it to make digestive juices and when it is supposed to send signals to the brain informing it about hunger or satisfaction.

There are nerves connecting the central nervous system which is the spinal cord and the brain, to the digestive system and it controls certain digestive functions as well an example is salivating. Enteric nervous system(ENS) nerves exist within the walls of the GI tract, the nerves of the ENS has the ability to release different substances that could speed up or delay food movement and production of digestive juices. The existing nerves then sends signals to help control the actions of the gut muscles on when it is supposed to contract, relax and then push forward through the intestines.

Age and Digestion.

Age they say changes so many things, this can affect the digestive system as well. The first noticed symptom begins in the mouth and this could link up to affecting other digestive system process, the taste bud begins to get less sensitive, food becomes less appetizing as they used to be, then there is loss of teeth, disease of the gums and the salivary glands that fail to produce sufficient saliva.
The process of swallowing then becomes difficult, ingested food then begins to slowly move through the alimentary canal as a result of reduced strength as well as reduction in the tone of muscular tissue.

Neurosensory feedback also gets dampened, the transmission of messages that stimulates the release of enzymes and hormones are slowed down. Large intestinal issues begin to come up as well, we have cases of; diverticulitis disease, constipation, and hemorrhoids. Health conditions can also begin to affect the accessory organs and their abilities to deliver pancreatic enzymes and bile into the small intestine as required, the health issues that can arise are; jaundice, acute pancreatitis, gallstones and cirrhosis.

The process of digestion includes both the chemical and mechanical processes. The mechanical process of digestion is basically physical, in this process, the chemical nature of food remains unchanged. Instead, food is made to increase both on the surface area and mobidity. Mechanical digestion is not only limited to the first process of food digestion, it goes further to the point when the food leaves the mouth.
There is a mechanical process of food churning that happens in the stomach, splitting it apart and exposing the surface area to digestive juices creating a form of acidic soup called chyme.

Chemical digestion begins in the mouth, breaking down complex food molecules into chemical building blocks. When food substances gets broken down in the body, they have no value to the body until they enter into the blood stream and their nutrients are put to work, the process can only be put to work through the process of absorption, which primarily takes place in the small intestine. It is at the small intestine that majority of the nutrient gets absorbed from the lumen of the alimentary canal into the bloodstream through the epithelial cells making up the mucosa. Lipids gets absorbed into lacteals and they get transported through the lymphatic vessels into the bloodstream.

Conclusion.

In a more simplified manner, I have been able to do adequate justice to the topic at hand, there is so much beyond food intake and waste excretion as described above, if you have read my post up till now, then I want to say a big thank you and I cannot wait to make friends here.

References.

https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/digestive-system

https://www.niddk.nih.gov/health-information/digestive-diseases/digestive-system-how-it-works

https://courses.lumenlearning.com/suny-ap2/chapter/digestive-system-processes-and-regulation/

https://guides.hostos.cuny.edu/bio140/5-16

https://www.webmd.com/heartburn-gerd/your-digestive-system