3.1 Digestive System Flashcards
Mechanical digestion
Involves the physical breakdown of food into very small pieces.
Chemical Digestion
Involves the breakdown of large particles into smaller particles by substances called enzymes.
Food’s path to stomach
The digestive system is actually a long tube, with a few attachments along its length. It starts at your mouth and finishes at the rectum.
What happens before the food reaches your stomach?
It comes in contact with many organs. Digestion begins at the entrance to the tube, the mouth, with the mechanical breakdown of your food.
What do your teeth do?
teeth mechanically digest the food by grinding it and mixing it with saliva
What does saliva do?
Three pairs of salivary glands are located in the tissues. surrounding your mouth to produce saliva.
What does Saliva contain?
Saliva contains water to moisten the food, making the food easier to swallow. It also contains, an enzyme known as salivary amylase.
What does this enzyme do?
This enzyme chemically digests large starch molecules into smaller sugar molecules
What happens as you swallow?
As you swallow, a flap of skin called the epiglottis moves across your windpipe, and food is funneled into the esophagus.
Peristalsis
Is caused by contractions of muscle tissue that lines the esophagus.
Gastric juice
Is composed of mucus, hydrochloric acid, water, and digestive enzymes. The hydrochloric acid, along with the enzymes, chemically digests proteins into smaller particles
What does mucus do?
The mucus helps to prevent the gastric juice from digesting the stomach itself. The stomach slowly releases the food, which is now a liquid, into the small intestine
What does the pancreas do?
The pancreas sends digestive enzymes into the small intestine.
What do these enzymes do?
These enzymes, complete the breakdown of starches and proteins into very small particles.
What does the liver produce?
The liver produces a substance called bile, which is stored in the gall bladder.
