Human digestive system

  1. Your Digestive System and How it Works
  2. The Digestive System – Human Nutrition


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Your Digestive System and How it Works

How Long It Takes for Food to Digest The time it takes for food to digest can vary a bit from person to person, and between males and females. Studies have shown that the entire process takes about an average of 50 hours for healthy people, but can vary between 24 and 72 hours, based on a number of factors. Why Digestion Is Important We eat because we need nourishment but our food isn't something our bodies can easily assimilate into our cells. It is digestion that takes our breakfast and breaks it down. Once it's broken down into parts, it can be used by the body. This is done through a chemical process and it actually begins in the mouth with saliva. • Mouth: Food breakdown begins with chewing and the mixing of food with saliva. Once the food is chewed sufficiently, we voluntarily swallow it. After that, the digestive process is involuntary. • Esophagus: Once the food is swallowed, it travels down the • Stomach: In digestion, the stomach is where the rubber meets the road. There are • Small intestine: Once food reaches the • Large intestine: The large intestine doesn't do much digesting, but it is where a lot of liquid is absorbed from the waste material. Undigested materials are moved through, which can take a day or more, and then into the last part of the colon, which is the rectum. When there is stool in the rectum, it precipitates an urge to defecate, and finally, the waste materials are expelled out through the anus as a bowel movement. A Word From Verywell The dig...

The Digestive System – Human Nutrition

The Digestive System The process of digestion begins even before you put food into your mouth. When you feel hungry, your body sends a message to your brain that it is time to eat. Sights and smells influence your body’s preparedness for food. Smelling food sends a message to your brain. Your brain then tells the mouth to get ready, and you start to salivate in preparation for a meal. Once you have eaten, your digestive system (Figure 2.4 “The Human Digestive System”) starts the process that breaks down the components of food into smaller components that can be absorbed and taken into the body. To do this, the digestive system functions on two levels, mechanically to move and mix ingested food and chemically to break down large molecules. The smaller nutrient molecules can then be absorbed and processed by cells throughout the body for energy or used as building blocks for new cells. The digestive system is one of the eleven organ systems of the human body, and it is composed of several hollow tube-shaped organs including the mouth, pharynx, esophagus, stomach, small intestine, large intestine (colon), rectum, and anus. It is lined with mucosal tissue that secretes digestive juices (which aid in the breakdown of food) and mucus (which facilitates the propulsion of food through the tract). Smooth muscle tissue surrounds the digestive tract and its contraction produces waves, known as peristalsis, that propel food down the tract. Nutrients, as well as some non-nutrients, are...