Digestive System

what structures make up the GI tract and their function

mouth, pharynx, esophagus, stomach, small intestine, large intestine and it transports, digest and absorbs food

what are the accessory organs of the digestive system and their function?

liver, gallbladder, salivary glands, pancreas, teeth, tongue and assist with digestion

what are the steps of digestion?

ingestion, secretion, motility, digestion, absorption, excretion

what are the four layers of the GI tract?

mucosa, submucosa, muscularis externa, serosa

what is the mucosa?

thin layer of smooth muscle that alters the shape of the lumen

what is the function of the submucosa?

supply the mucosa with oxygen, nutrients and removes waste

what is the function of the submucosal plexus?

alters exocrine and endocrine secretion

what is the function of myenteric plexus?

alters gut motility via muscularis externa

what is the function of the muscularis externa?

drives motility in the GI tract

what is the function of the serosa (adventitia)?

mesenteries that anchor and supply blood to the abdominopelvic organs

How does the enteric nervous system contribute to digestion?

regulates local digestive function of secretion and motility

how does the autonomic system contribute to digestion?

alters digestive activity through sympathetic and parasympathetic input

what major structures of the cephalic phase detects stimulus?

cerebrum, hypothalamus, medulla

what cranial nerves are involved in salvation reflex?

facial, glossopharyngeal and vagus nerve

which cranial nerve is involved in increasing gastric acid secretion?

vagus nerve

what is the function of the incisors teeth?

cutting and slicing food

what is the function of the canine tooth?

tearing food

what is the function of premolars?

tearing and crushing food

what is the function of molars?

grinding food

what is the enamel?

hardest substance in the body

what is function of pulp chamber?

house blood vessels and nerves of the tooth

what is the function cementum?

anchors tooth

what is the function of root canal?

allows blood vessels and nerves into teeth

what does salivary amylase and lingual lipase act on and its product?

breaks down polysaccharides and triglyceride into disaccharide, a-dextrin and fatty acids and diglyceride

what are the salivary glands?

parotid, submandibular and sublingual gland

what is the composition of saliva?

95.5 % water and 0.5% solutes

what is the function of alkaline mucus secreted by goblet cells?

acts as physical barrier between the stomach and epithelium

what is the function of parietal cells?

secrete gastric acid and intrinsic factors

what is the function of chief cells?

secrete pepsinogen

what is the function of D cells?

secrete somatostatin which inhibits acid secretion

what is the function of G cells?

secrete gastrin which stimulates acid secretion

which substance can be absorbed in the stomach?

aspirin, vitamin B12, alcohol

what causes ulcer?

Helicobacter pylori bacteria

what causes heartburn

acid reflex due to opening in the lower esophageal sphincter

what is the function of the hepatic portal vein?

process nutrients from the GI tract and detoxify drugs and toxins

what is the flow of blood in the hepatic vein?

hepatic artery, central vein, hepatic vein, inferior vena cava, right atrium

what is the function of portal vein branch?

it brings in nutrients and toxins for filtration

what is the function of hepatic artery branch?

carries oxygen to hepatocytes

what is the function of central vein?

transports filtered oxygen poor nutrient rich blood

what is the function of Kupffer cells?

assist the liver in its digestive and nondigestive function

what is bile composed of?

emulsifying bile salts and bilirubin from heme

what is the immunological and metabolic function of hepatocytes?

cholesterol metabolism, lipid metabolism, detoxification, endotoxin removal

what is the function of hepatocytes (immunological)?

acute phase response, clotting factor production, complement protein production, antigen presentation

what is the attachment site of lesser omentum?

lesser curvature of the stomach to liver

what is the attachment site of mesentery proper?

small intestine to posterior abdominal wall

what is the attachment site of the greater omentum?

greater curvature of the stomach to transverse colon