AB Flashcards
Primary function of the GI system
Brings nutrients into body, to be used for maintenance, function and growth of cells
What does Visceral peritoneum line….
organs
Parietal peritoneum lines….
Body wall
What are the mesenteries
Double fold of peritoneum
Two types of digestion
- Mechanical – motility patterns
2. Chemical – secretions
Where does absorption take place
- Stomach:
- Small intestine:
- Larger intestines:
What are the 4 layers of the digestive tract (in order)
- Mucosa
- Submucosa
- Muscularis
- Adventitia
what layer is the most important in the oesophagus in peristalsis
muscularis
What are the three layers of muscularis externa
- Longitudinal (outer)
- Circular ( middle)
- Oblique (inner)
What do parietal cells secrete
hydrochloric acid (HCI)
What do G cells secrete
secretes gastrin (regulates acid and secretion)
what do chief cells secrete
secrete pepsinogen (enzyme that digests proteins)
Rings of smooth muscle called _____ regulate the movement of luminal contents from one region to the next
Sphincters
What are Rugae
Mucosal folds in stomach that allow distension
P______ S______ controls rate that chyme is released into the small intestine
Pyloric sphincter
where is chyme stored
stomach
1st segment of the small intestines
Duodenum
- Receives chyme from stomach (chyme is food mixed with stomach acid – start of break down)
2nd segment of small intestines
Jejunum
- Mostly chemical digestion and nutrient absorption
largest segment of small intestines
Ileum
- Absorbs vitamin B12, bile salts and remainder of nutrients
Absorption takes place in small intestines
- Smooth muscle -> allows propulsion of food through the tube
- A large surface area -> tube length, plicae, villi and microvilli
what are Plicae Circulares
folds of the sub mucosa and is covered in villi (mostly in jejunum
Intestinal villi contains L_____ and capillary network to absorb fats and nutrients
lacteal
the surface of intestinal villi consists of S_____ C_______ epithelium with m_____
simple columnar epithelium with microvilli
- which absorb nutrients
Microvilli are called “_____ _____”
“Brush Border”
- epithelial cells absorb nutrients
