The Process of Human Digestion
The Process of Human Digestion
Digestive System, series of organs put together that purpose is to break down, or digest, the food we eat. Food is made up of large things called, complex molecules, which the digestive system breaks down into smaller things called simple molecules that get absorbed into the bloodstream. The bloodstream is our blood. The simple molecules travel through the bloodstream to all of the parts of the body, which we use for growth, repair, and energy. All living things that eat to get energy have a digestive system, a feature that makes us different from plants. Plants make their own food in a process called photosynthesis, photosynthesis is when plants make sunlight to convert water and carbon dioxide into simple sugars. But animals, including humans, must take in food in the form of organic matter, such as plants or other animals.
Digestion generally involves two parts: a mechanical part and a chemical part. In the mechanical part, teeth physically break down large pieces of food into smaller pieces. In the chemical part, digestive chemicals called enzymes break apart individual molecules of food to yield molecules that can be absorbed and distributed throughout the body. These enzymes are secreted by glands in the body. The digestive system of most animals consists mainly of a long, tube called the alimentary canal, or digestive tract. This canal has a mouth at one end, through which food is taken in, and an anus at the other end, through which pup is taken out the body.. Muscles in the walls of the alimentary canal move the food along. Most digestive organs are part of the alimentary canal.
However, two digestive organs, the liver and pancreas, are located outside the digestive system. These organs put in chemical digestion by releasing digestive juices into the digestion system through tubes called ducts.
If an adult’s digestive tract were stretched out, it would be 20 to 30 ft long. In humans, digestion begins in the mouth, where both mechanical and chemical digestion occur. The mouth quickly turns food into a soft, moist mass. The muscular tongue pushes the food against the teeth, which cut, chop, and grind the food. Glands in the cheek linings secrete mucus, which lubricates the food, making it easier to chew and swallow. Three pairs of glands empty saliva into the mouth through ducts to moisten the food....