Digestive Flashcards
What are the macronutrients
carbs, proteins, fat
What are micronutrients
vitamins
What is the alimentary canal
the 30 ft tube that ingested material passes through: mouth, pharynx, stomach, LI, SI
What are some accessory structures
teeth, tongue,gallbladder,salivary glands, liver (not part of the tube)
What are the 6 digestive processes
- ingestion
- Propulsion
- Mechanical digestion
- Chemical digestion
- Absorption
- Defication
What is deglutition
swallowing
What is peristalis
series of wave-like muscle contractions that moves food to different processing stations in the digestive tract
What are the 4 layers of the small intestine
- Mucosa
- Submucosa
- Muscularis Externa
- Serosa
What are the 3 sublayers of the mucosa
- epithelium: Simple columnar, goblet cells, enteroendocrine cells that produce hormone
- lamina propria: loose CT w/ much nerves/cap/lymph
- Muscularis mucosae: thin layer of muscle. (not main muscle layer)
What is the function of the mucosa
secretion(mucus, enxymes, hormones) and absorption
What is the submucosa
layer of dense ct.
extensive vascualar system to transport absorbed materials
What is the muscularis externa
responsible for gut motility for peristalsis
What is the serosa
layer of loose (areolar) connective tissue
- forms part of the peritoneum
- above diaphragm, the lining is fibrous connective tissue called the ADVENTITIA
What is the enteric nervous system
the system that regulates the motility, secretions and blood flow to the digestive system
What are the two networks that are a part of the parasympathetic nervous system (in the enteric nerv. sys.)
- Submucosal nerve plexus
2. Myenteric nerve plexus
What is the submucosal nerve plexus
- in submucosa
- sensory and motor
- regulates glands and the smooth muscles in the mucosa
What is the myenteric nerve plexus
- between layers of the muscularis externa
- controls peristalsis
What is the mesentery?
a double layer of peritoneum that extends from the peritoneum of the body wall to the dig. organs (path for nerves, lmyph and fat storage)
What is the lesser omentum
mesenteric tissue extending from the stomach up to the liver
what is the greater omentum
layer of fat hanging down from the stomach that covers intestines like an apron
How many deciduous (baby) are there
20
How many permanent teeth are there
32
Incisors
sharp teeth used for cutting, to bite off a piece of food
Canines
more pointed teeth to puncture and shred food
premolars (biscuspis) and molars
flat broad surfaces for grinding and chewing food
What does the pharynx do
connects the oral cavity to the esophagus
What does the esophagus do
connects the pharynx to the stomach
does digestion or absorption occur in the esophagus ?
heck no
How much can your stomach hold
4 liters(50ml when empty)
What are the 4 regions of the stomach
- Cardiac region
- Fundic region
- Body
- Pyloric region
What is the inner lining in the stomach that stretches as the stomach fills
rugae
cardiac region
small area where the esophagus goes into the stomach
fundic region
dome-shaped upper portion
body
bulk of the stomach
pyloric region
narrow pouch at the end
What does the chief cells do
-produce pepsin (a protease) and gastric lipase at the base of gastric glands
What do parietal cells do
secrete HCI giving the pH of 1.5-3.0
-Secretes intrinic factor (needed for 12 absorpt)
What do mucous cells do
produce acidic mucous
what do enteronedocrine cells do
produces over 20 hormones inculding gastrin, serotonin, cholecystokinin CCK
What are the circular folds of the SI
plicae
-causes chyme to spiral
What are the major brush border enzymes
maltase sucrase lactase aminopeptidase dipeptidases
Where does the illeum enter the LI
ileocecal valce
What are the liver lobes separated by
the falciform ligament
What is the livers only digestive function
produce bile
review ducts
for real
What produces bile
liver
what secretes bile
gallbladder
What does the pancreas do
releases pancreatic juice into the duodenum
NaHCO3
buffers the chyme
-released in pancreatic juice
Digestive enzymes
-released in pancreatic juice
Secretin
released from duodenum
- Stimulated release by acid*
- bicarbonate-rich pancreatic juice*
Cholecystokinin (CCK)
- stimulated release by protein and fat*
* enzyme rich pancreatic juice*
Protease
Protein breaking enzyme
Amylase
Starch breaking enzyme
Lipase
Fat breaking enzyme
What is maltase made of
glucose + glucose
What is sucrase made of
glucose + fructose
What is lactase made of
glucose + glactose
carboxypeptidase, aminopeptidase, and dipeptidases
brush border enzymes that break down proteins
what are the things responsible for fat digestion
lingual lipase, gastic lipase, and PANCREATIC LIPASE
what happens when lipid is broken down
TWO fatty acids and one monoglyceride
