digestive system Flashcards
functions of digestive system
Mechanical and chemical breakdown of food and the absorption of nutrients
Excretion of waste
types of bowel movements
Mixing Movements:
mix food with digestive juice
Propelling Movements:
called peristalsis; pushes food down the tube
mouth
begins digestion by chewing and mixing with saliva
tounge
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.
regions of stomach
cardia, fundus, body, pylorus
pyloric canal
which connects to the duodenum.
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
is 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
which is the primary digestive organ in the body. Not only is this where most digestion occurs, it is also where practically all absorption occurs.
duodenum
which begins at the pyloric sphincter. Just past the pyloric sphincter, it bends posteriorly behind the peritoneum, becoming retroperitoneal, and then makes a C-shaped curve around the head of the pancreas before ascending anteriorly again to return to the peritoneal cavity and join the jejunum.
jejunum
is about 0.9 meters (3 feet) long (in life) and runs from the duodenum to the ileum. Jejunum means “empty” in Latin and supposedly was so named by the ancient Greeks who noticed it was always empty at death.
lleum
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
s 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
Diagnostic medical tool designed to classify the form of human feces into seven categories.
liver
is the largest gland in the body, weighing about three pounds in an adult.
gallbladder
stores and concentrates bile, releasing it when it is needed by the small intestine.
pancreas
is responsible for secretion of digestive enzymes and bicarbonate