Download Digestion

Class Notes – Digestion
“Digestion”
o The process by which food is converted into substances that can be absorbed and
assimilated by the body, through the Alimentary Canal (starting in the attic & finishing in
the basement)
“Quick Facts”
o For a healthy person, Digestion can take 24-48 hours to complete.
o The process of digestion allows us to take out and use the important nutrients that
foods contain.
“Steps in the Digestive Process”
1. Digestion starts in the Mouth, where food is broken down into smaller pieces by the
grinding of teeth and softened by saliva.
o The mouth produces 2.5 bathtubs of saliva every year!
2. Food then moves past the Epiglottis, which is a leaf-shaped piece of cartilage that blocks
the wind pipe when we swallow.
3. Food moves from the mouth to the stomach through the Esophagus.
4. Once in the Stomach, food is partially broken down through the muscle contractions of
the stomach and converted into a liquid through the release of acids and enzymes.
5. Food then enters the Small Intestine, where finger-like projections , called Villi, suck out
the nutrients.
o The Small Intestine is roughly 20 feet long, that long distance allows for more
nutrients to be sucked out of the food.
6. After all the nutrients have been taken out, the “leftovers” enter the Large Intestine,
where any excess moisture is removed.
7. The dried out “leftovers” then enter the Rectum, until they are evacuated from the
body.
“Friends of the Digestive Process”
1. Liver: Nutrients that are taken out in the small intestine through the villi, are sent to the
liver, where they are then sent throughout the body.
2. Gallbladder: The liver also produces Bile. Bile is a fluid that is made and released by the
liver and stored in the Gallbladder. Bile helps with digestion. It breaks down fats into
fatty acids, which can be taken into the body by the digestive tract.
3. Pancreas: The Pancreas secretes digestive juices into the small intestine, which help
breakdown proteins, carbohydrates and fats. The Pancreas also produces and secretes
the hormones Insulin and Glucagon into the bloodstream. These two hormones play an
important role in maintaining a normal blood sugar level.