Digestive System Flashcards
Functions of Digestive System
- Mechanical and chemical breakdown of food and the absorption of nutrients
- Excretion of waste
Two types of bowel movements
-Mixing Movements:
mix food with digestive juices
-Propelling Movements:
called peristalsis; pushes food down the tube
Mouth
Begins digestion by chewing and mixing with saliva
Tongue
Moves food, connects to floor of mouth via frenulum
Amylase
Enzyme breaks down starch into sugars
Esophagus
The muscular tube that carries food and liquids from your mouth to the stomach
Four regions of the stomach
- The cardia (or cardiac region) is the point where the esophagus connects to the stomach and through which food passes into the stomach
- Located inferior to the diaphragm, above and to the left of the cardia, is the dome-shaped fundus
- Below the fundus is the body, the main part of the stomach
- The funnel-shaped pylorus connects the stomach to the duodenum. The wider end of the funnel, the pyloric antrum, connects to the body of the stomach
Pyloric canal
The narrower end is called the pyloric canal, which connects to the duodenum
Pyloric sphincter
The smooth muscle pyloric sphincter is located at this latter point of connection and controls stomach emptying
Stomach lining
Mucus prevents stomach from digesting itself, small openings called gastric pits contain glands
Pepsin
Most important digestive enzyme for breaking down food
Mechanical Digestion
Food being broken down in smaller pieces (ex: chewing and churning of the stomach)
Chemical Digestion
Substances in our digestive organs are released that change food particles into particles that are chemically different (ex: acids and bases)
Chyme
The semi-fluid mass of partly digested food that is expelled by a person’s stomach, through the pyloric valve, into the duodenum
Small Intestine
the longest segment of the gastrointestinal tract — the long, continuous pathway that food travels through your digestive system. In the small intestine, food is broken down into liquid and most of its nutrients are absorbed
Duodenum
The shortest region is the 25.4-cm (10-in) duodenum,
Jejunum
The jejunum is about 0.9 meters (3 feet) long (in life) and runs from the duodenum to the ileum. Jejunum means “empty” in Latin
Ileum
The ileum is the longest part of the small intestine, measuring about 1.8 meters (6 feet) in length. It is thicker, more vascular, and has more developed mucosal folds than the jejunum
Large Intestine
The large intestine is subdivided into four main regions: the cecum, the colon, the rectum, and the anus
Cecum
Start of large intestine, has an attached appendix
Colon
4 sections:
- Ascending
- Transverse
- Descending
- Sigmoid
Rectum
Stores waste before it is expelled from the body
Anus
Muscular sphincter which controls the exit of waste
Bristol Stool Chart
Type 1 and 2 - Constipation Type 3 and 4 - Normal Type 5 - Lacking Fiber Type 6 - Mild Diarrhea Type 7 - Severe Diarrhea
Liver
The liver is the largest gland in the body, weighing about three pounds in an adult. It is also one of the most important organs. In addition to being an accessory digestive organ, it plays a number of roles in metabolism and regulation
Gallbladder
The gallbladder stores and concentrates bile, releasing it when it is needed by the small intestine
Pancreas
The pancreas is responsible for secretion of digestive enzymes and bicarbonate
