chapter 38 part 1 Flashcards
what is the length of the GI tract
7 to 7.9 meter / 23-26 feet
it is located in the MEDIASTINUM, anterior to the spine and posterior to the trachea and heart
esophagus
size of esophagus
25 cm
the diaphragm at an opening
diaphragmatic hiatus
can be ‘found at the left upper portion of the abdomen’ under the left lobe of the liver and the diaphragm, overlaying most of the pancreas
stomach
what is the capacity of the stomach
1500 ml
stores food during eating, secretes digestive fluids, and propels the partially digested food, or chyme, into the small intestine
stomach
stomach has four anatomic regions:
cardia
fundus
body
pylorus
what is the entrance of the stomach
cardia
what is the exit of the stomach
pylorus
longest segment of the GI tract
small intestine
what is the length of small intestine
70m
the process by which ‘nutrients enter the bloodstream’ through the intestinal walls
absorption
three sections of small intestine:
duodenum
jejunum
ileum
most proximal section of small intestine:
duodenum
middle section of small intestine:
jejunum
distal section of small intestine:
ileum
controls the flow of digested material from the ileum into the cecal portion of the large intestine and prevents reflux of bacteria into the small intestine
valve/sphincter
consists of an ascending segment on the right side of the abdomen
large intestine
terminal portions of the large intestine:
sigmoid colon
rectum
anus
blood flow to the GI tract is about ____ of the total cardiac output and increases significantly after eating
20%
what nerve stimulation causes peristalsis and increases secretory activities
parasympathetic nerve stimulation
give functions of the digestive system:
breakdown for digestion
absorption
elimination
the process of digestion BEGINS with this act
chewing
the process that the ‘food is broken down into small particles’ that can be swallowed and mixed with digestive enzymes
chewing
an enzyme that begins the digestion of STARCHES
ptalyn/salivary amylase
help LUBRICATE the food as it is chewed, thereby facilitating swallowing
water and mucus
Swallowing begins as a voluntary act that is regulated by the ________ of the central nervous system (CNS)
medulla oblongata
closes tightly to
prevent reflux of stomach contents into the esophagus
lower esophageal sphincter
