The main purpose of the digestive system is to break down food automatically through the use of enzymes, so the food can be used by the body for cell energy and growth and repair. The human digestive system comprises of many different organs, glands, and procedures to decompose food into smaller particles. These smaller particles of food broken down by the digestive system creates energy, produces nutrition, and excrete consumed and created waste for the body. Humans simply could not physically grow, repair, rid of toxic waste, or survive without the digestive system.
Where does human digestion take place?
The digestion of food mostly takes place within a course of tubes such as the smaller intestines, stomach, and esophagus all directly behind the abdomen. Food gets digested as it goes through each of the body's digestive organs. While most of these tube-like organs digest and exact nutrients from the food; there are other digestive organs food passes through like the liver and pancreas that produce or store digestive compounds. All the digestive organs basically take food through a long twisting tube that runs from the mouth to the anus.
How does the digestive process work?
The human digestive process begins in the mouth- The process of chewing and the salivary enzymes such as lipase and amylase (which induce a chemical action upon food) produced by the salivary glands are used to break down food partly in the mouth. The enzymes made via salivary glands also decompose starches into smaller particles. Chewing represents an important time period in digestion because chewing happens before any other digestive process. The initial chewing process will determine how well food will be digested throughout the whole body. Plus, the act of chewing represents the part of the digestion where a person has the most control over. Be sure to chew food good and well to help make the job for the next organ easier.
Food enters the esophagus (Also known as oesophagus) after leaving the mouth- The long tube of the esophagus flows from the mouth to the stomach. The act of swallowing food stands as voluntary, and as soon as swallowing starts, the act becomes involuntary and continues under the authority of the nerves. Food in the esophagus gets forced down to the stomach by continual rhythmic waves of automatic muscle movement called peristalsis. Other organs from the kidneys to the bladder also use peristalsis. This automatic muscle movement gives humans the ability to eat even when they are upside down.
Food on the way to the stomach- In the passage that connects the stomach and ssophagus, there lies a ringlike valve (created by muscles) that shuts off the passage between the two organs. As food gets close to the closed ring valve, the muscles will open there by relaxing in order to allow food to pass into the stomach. The passage will close off again once the food has passed into the stomach.
Food in the stomach- The stomach acts as place where food can be stored that comes from the esophagus. A human stomach looks like a pouch (Or sack) connected with the throat. The upper region of the stomach has smooth muscles. These smooth muscles will relax in order to allow large amounts of food within the stomachs pouch. The lower region muscles contract in a rhythmical pattern to store and mix up food with digestive enzymes like pepsin, gelatinase, gastric amylase, and lipase. The stomach also mixes food in with very strong gastric acid (Also called hydrochloric acid) to turn the food into chyme. Chyme, which stands as partly digested food mixed with stomach acids, leaves stomach and heads to small intestine.
Food in the small intestine- A rhythmic smooth muscle contraction continues here in small intestine to guide food throughout it's tube. Enzymes from the pancreas and glands within the intestine walls will continue to break food down into carbohydrates and proteins. In the small intestine, the liver produces bile, which dissolves fat in food, to help food be further digested by other enzymes. Bile gets stored into the gall bladder (sac-like organ located by the duodenum) and completely digested food gets absorbed through the intestinal walls. During absorption, villi help quicken the absorbing process by increasing surface area of the intestine walls for the particles of digested food to go through. With the help of tiny finger-like projections called villi, which collect sugars and amino acids, food enters the blood flow of capillaries outside of the intestine.
Food in the large intestine- Once food passes through the small intestine, microbes like klebsiella, lactobacillus acidphilus, bacteroidesm, and escherichia coli continue to digest food here in the large instestine. The large instestine provides the body with it's last chance to gather any water, electrolytes (like sodium), and minerals from the remaining food. The rest of the unused content gets sent across the abdomen into the transverse colon. Then the waste will go to the descending colon (on the other side of the body) and pass into the sigmoid colon.
The end of the human disgestive process - The solid waste will end in up in the rectum (from the sigmiod colon) until ready to exit the body through the anus.
For Fun: Did you know? The tongue helps with digestion, even though, the tongue is not usually listed a part of the digestive tract. The tongue helps provide taste for the food, shift food around the mouth, and the mouth swallow the food by forcing it back toward the throat.
Did ou know? Food enters the duodenum (The gall bladder is located here) first, the jejunum, and then finally the ileum of the Small Intestine
References:
http://www.enchantedlearning.com/subjects/anatomy/digestive/ Here, this site has a fun digestive system glossary near the bottom of page to learn from.
No comments:
Post a Comment