The Digestive System: Mouth and Teeth

The Digestive System

• The digestive system is designed to transform food into useful nutrients that keep you energized and help your cells grow and repair.
• The mouth is the gateway to the digestive system, where food is broken down into pieces to make the process easier.
• Saliva mixes with food and breaks it down even more, making it easier for the stomach to digest.

The Mouth

• The amount of saliva produced in a year could fill 2 medium-sized bathtubs.
• Teeth chew food, and the tongue rolls it around to mix it with saliva.

The Throat (Pharynx)

• The throat is a fork in the road, where food can either go down the esophagus or into the lungs.
• Coughing can help dislodge food that goes into the lungs.

The Esophagus

• The esophagus is a muscular tube that uses peristalsis to move food through the digestive system.
• Peristalsis is a process where muscles in the esophagus squeeze behind the food and relax in front of it.

The Stomach

• The stomach is a muscular sac that holds, mixes, and grinds food into mush.
• Stomach acid is strong and can break down food, but it can also harm the stomach lining.
• The stomach has a valve that opens to let food in and keeps it from coming back out into the esophagus.

The Small Intestine

• The small intestine is a long, coiled tube that is over 20 feet in length when spread out.
• It has three sections and is responsible for absorbing nutrients from food.
• Bile from the liver and enzymes from the pancreas help break down fat and absorb nutrients.

The Large Intestine (Colon)

• The large intestine is a muscular tube that is 5-6 feet long and is responsible for absorbing water and electrolytes.
• It is home to trillions of bacteria that help break down food, absorb nutrients, and support immunity.
• The appendix is a small, dangly thing that houses bacteria and has some tissues useful for the immune system.

The Rectum

• The rectum is a straight chamber that is about 8 inches long and has special sensors that detect when there is stool or gas to be released.
• The sensors send signals to the brain, which then sends the urge to go to the bathroom.
• The sphincters relax to release stool, and contract to keep it in until the right moment.

Elimination

• The process of eliminating stool takes about 36 hours from the small intestine to the rectum.
• The rectum and sphincters work together to keep stool in until the right moment, and then release it when necessary.

The Digestive System

• Designed to transform food into useful nutrients for energy and cell growth/repair
• Begins in the mouth, where food is broken down into smaller pieces

The Mouth

• Saliva mixes with food to break it down further, making digestion easier for the stomach
• Teeth chew food, and the tongue rolls it around to mix it with saliva
• A person produces enough saliva in a year to fill 2 medium-sized bathtubs

The Throat (Pharynx)

• Acts as a fork in the road, where food can either go down the esophagus or into the lungs
• Coughing can help dislodge food that accidentally goes into the lungs

The Esophagus

• A muscular tube that uses peristalsis to move food through the digestive system
• Peristalsis is a process where muscles squeeze behind food and relax in front of it, pushing food forward

The Stomach

• A muscular sac that holds, mixes, and grinds food into mush
• Stomach acid is strong enough to break down food, but can also harm the stomach lining
• Has a valve that opens to let food in and keeps it from coming back out into the esophagus

The Small Intestine

• A long, coiled tube over 20 feet in length when spread out
• Has three sections responsible for absorbing nutrients from food
• Bile from the liver and enzymes from the pancreas help break down fat and absorb nutrients

The Large Intestine (Colon)

• A muscular tube approximately 5-6 feet long responsible for absorbing water and electrolytes
• Home to trillions of bacteria that help break down food, absorb nutrients, and support immunity
• The appendix is a small, dangly thing that houses bacteria and has some tissues useful for the immune system

The Rectum

• A straight chamber about 8 inches long with special sensors detecting stool or gas
• Sensors send signals to the brain, which then sends the urge to go to the bathroom
• Sphincters relax to release stool, and contract to keep it in until the right moment

Elimination

• The process of eliminating stool takes about 36 hours from the small intestine to the rectum
• The rectum and sphincters work together to keep stool in until the right moment, and then release it when necessary

The Digestive System

• Designed to transform food into useful nutrients for energy and cell growth/repair
• Begins in the mouth, where food is broken down into smaller pieces

The Mouth

• Saliva mixes with food to break it down further, making digestion easier for the stomach
• Teeth chew food, and the tongue rolls it around to mix it with saliva
• A person produces enough saliva in a year to fill 2 medium-sized bathtubs

The Throat (Pharynx)

• Acts as a fork in the road, where food can either go down the esophagus or into the lungs
• Coughing can help dislodge food that accidentally goes into the lungs

The Esophagus

• A muscular tube that uses peristalsis to move food through the digestive system
• Peristalsis is a process where muscles squeeze behind food and relax in front of it, pushing food forward

The Stomach

• A muscular sac that holds, mixes, and grinds food into mush
• Stomach acid is strong enough to break down food, but can also harm the stomach lining
• Has a valve that opens to let food in and keeps it from coming back out into the esophagus

The Small Intestine

• A long, coiled tube over 20 feet in length when spread out
• Has three sections responsible for absorbing nutrients from food
• Bile from the liver and enzymes from the pancreas help break down fat and absorb nutrients

The Large Intestine (Colon)

• A muscular tube approximately 5-6 feet long responsible for absorbing water and electrolytes
• Home to trillions of bacteria that help break down food, absorb nutrients, and support immunity
• The appendix is a small, dangly thing that houses bacteria and has some tissues useful for the immune system

The Rectum

• A straight chamber about 8 inches long with special sensors detecting stool or gas
• Sensors send signals to the brain, which then sends the urge to go to the bathroom
• Sphincters relax to release stool, and contract to keep it in until the right moment

Elimination

• The process of eliminating stool takes about 36 hours from the small intestine to the rectum
• The rectum and sphincters work together to keep stool in until the right moment, and then release it when necessary