Lab 8 Digestive Flashcards
What is digestion
process of breaking down food molecules that can be absorbed.
what is ingestion
food into mouth
what is propulsion
food moves through GI tract
what is mech. digestion
physical breakdown of food into smaller pieces
what is chem. digestion
breakdown of bonds in food molecules
what is secretion
release of chem/enzymes into the lumen go GI tract
what is absorption
movement of nutrients across mucosa into blood/lymph
what is defection
elimination through rectum/anus
What are the 4 layers of the GI tract
1) Mucosa (3 layers)
2) Submucosa
3) Muscularis externa (2 layers
4) Serosa/ visceral peritoneum
what are the the 3 layers of the mucosa from deep to superficial
1) mucosa epithelium (stratified squamous or simple columnar)
2) Lamina propria (areolar CT)
3) muscular mucosae (thin layer of smooth muscle)
what is submucosa made of & what does it house
- dense irreg Ct
- houses vasculature & nerves
what are the 2 layers of muscularis externa
Circular (inner)
Longitudinal (outer)
what is peristalsis
GI movement in 1 direction by longitudinal muscles
what is segmentation
GI movement in both directions by circular muscles
what is the serosa made of
areolar CT & simple squamous
-mesentaries attach
what are mesenteries
double layer of peritoneum
anchor most of the organs in the abdominopelvic cavity to parietal peritoneum
where is greater omentum
drapes over top of the coils of the small intestine
where is the lesser omentum
stabilizes position of stomach
what does the mesentery proper do
binds sm. intestine to post. ab wall
what does the mesocolon do
binds lrg. intestine to post. ab. wall
what does the falciform ligament do
stabilizes position of liver
what is the tissues of the mouth & pharynx
stratified squamous
what is the function of the oral cavity
food is analyzed (sensory receptors for gustation) & lubricated. Digestion is initiated
- Mastication for physical digestion
- soluabalizing to form bolus
- Lingual lipase -enzymatic of lipids
- salivary amylase - enzymatic of starch
what is the function of the tongue
- manipulate food into bolus
- papillae grip food
- move food to back of mouth
where are taste buds located
between papillae
how many adult & baby teeth
(32 adult) (20baby)
how many incisors & what do they do
cut (2 sets)
how many canines & what do they do
tear/perice (1 set)
how many premolars & what do they do
crush (2 sets)
how many molars & what do they do
(3 sets) grind
what does the lingual frenulum do
attaches tongue to bottom of oral cavity
what is the function of the esophagus
move bolus to the stomach
the esophagus passes through which 2 ventral body cavities
thoracic & peritoneal
what is esophageal hiatus
opening in diaphragm that esophagus passes though on it’s way to ab. cavity
what lines the esophagus
stratifies squamous
what kind of digestion occurs in the stomach
- enzymatic digestion of protein by pepsin
- mechanical digestion vis churning
what tissue lies the stomach
-simple columnar
what does the mucous neck cells of the stomach do
secrete mucous
what do the parietal cells of the stomach do
secrete HCL
what do the cheif cells of the stomach do
secret pepsinogen - activated into pepsin by HCL
what do the G cells do
secret gastrin (stimulates secretion of gastric secretions & increases peristalsis)
What are the 3 stuctures in the Small intestine that increase SA
- Plicae circularis
- Villi
- microvilli
what do plicae circularis do
they are large folds of mucosal membrane
what are villi
finger like projections of mucosal surface
what are microvilli
“brush boarder” part of villi cells
what are the parts of the villus
lacteal - absorbs fat
capillary plexus
intestinal crypt - secretes digestive enzymes (alkaline)