The Digestive System Functions 1 Breaks down food
The Digestive System Functions: 1) Breaks down food into molecules the body can use. 2) Absorbs nutrients into the blood 3) Eliminates wastes from the body
Digestion Two types of digestion: 1) Mechanical: physical breaking apart of food Ex: Chewing, “Smushing”
Digestion Two types of digestion: 2) Chemical: enzymes break food into molecules Ex: saliva, stomach acid
The Digestive Journey 1) Digestion begins at the mouth. 1) Teeth: mash and grind food 2) Salivary Glands: make saliva, which breaks down food & makes it easier to swallow
2) After food is swallowed, it travels through the esophagus. – Food is moved through this tube by muscles contracting and squeezing. This process is called peristalsis – The esophagus delivers food to the stomach
3) The stomach is primarily composed of muscles. • Food is digested by mechanical and chemical digestion until it turns into a soupy substance called chyme.
4) Small Intestine • The nutrients in chyme are absorbed into the bloodstream through the walls of the small intestine.
Absorption • Digestive juices from the liver and pancreas join the chyme. • This turns the chyme into molecules small enough to get in blood.
Absorption • Villi: small, fingerlike projections, that help small intestine absorb nutrients
5) Large Intestine • Waste enters the large intestine as a soupy material, but it is changed into a semisolid waste called feces or stool.
• The rectum is the last part of the large intestine. It stores feces until it can be expelled. • Feces pass through to the outside of your body through an opening called the anus.
Other Digestive Organs Liver: Makes bile (fluid that helps digest)
Other Digestive Organs • Gall Bladder: stores and releases bile
Other Digestive Organs • Pancreas: Produces enzymes to help digest food
Other Digestive Organs • *Food does not pass through the liver, gall bladder, or pancreas.
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