digestive system Flashcards
1
Q
mucus cells
A
- secrete mucus
- lubricates and protects the stomachs epithelial lining
2
Q
chief cells
A
- secretes pepsinogen
- activated by low pH in stomach
- converts to pepsin (digests proteins)
3
Q
parietal cells
A
secretes HCl
4
Q
G cells
A
secretes gastrin, which stimulates parietal cells to secrete stomach acid
5
Q
small intestine
A
- food enters from the stomach through the pyloric sphincter
- most digestion and absorption occurs here
- villi increase surface area, increasing absorption
- each villi has microvilli
6
Q
3 segments of the small intestine
A
- duodenum
- jejunum
- ileum
7
Q
duodenum
A
continues breakdown of starches and proteins and remaining food types (majority of digestion)
8
Q
jejunum
A
majority absorption of nutrients occurs here
9
Q
ileum
A
absorption continues; contains Peyer’s patches (lymphoid tissue)
10
Q
large intestine
A
- enters from small intestine via the ilocecal valve
4 segments: - ascending, transverse, descending, and sigmoid
- large intestine stops at rectum
- functions: water and electrolyte absorption
- symbiotic bacteria aid in digestion and provide vitamin K and B12
11
Q
liver
A
- produces bile, which contains no digestive enzymes but emulsifies fats (mechanical digestion) and contains sodium bicarbonate
- bile: created in liver, stored in gall bladder
- if bile cannot be released, lipid breakdown would be compromised
12
Q
biliary flow
A
- cystic duct + hepatic duct –> common bile duct
- common bile duct + pancreatic duct –> secretes into duodenum
13
Q
pancreas
A
- secretes bicarbonate and digestive enzymes to the duodenum
** digestive enzyme flow**:
produced in pancreas –> flow from pancreatic duct into duodenum –> neutralizes acidic chyme from stomach and allows for digestion to occur
14
Q
digestive enzymes in pancreas
A
- trypsin/chymotrypsin
- lipase
- amylase
- nucleases
15
Q
trypsin/chymotrypsin
A
digest proteins
