digestive system Flashcards
salivary enzymes?
-Amylase = breaks down carbohydrate
-Lingual lipase = breaks down fats
-Lysozyme = disintegrates many bacteria and prevents
the overgrowth of oral microbial populations in the mouth.
3 types of salivary glands?
-Parotid
-sublingual
-Submandibular
liver
-regulation of nutrients in the blood
-blood glucose level
-blood lipid level:relase of lipid reserve
-blood protein level:convert amino acids into proteins
-blood fat soluble vitamins
-deactivates, stores, converts toxins for excretion
-synthesis&secretion of lymphocytes
large intestine
-chyme from small intestine –> large at the cecum
gallbladder
-bile synthesized in the liver is stored here
-released via bile duct
-emulsifies fat molecules into smaller droplets
colon
1)ascending colon
2)transverse colon
3)descending colon
4)sigmoid colon
various peritoneums in the abdominal cavity
-Parietal layer: The outer layer that lines the abdominal and pelvic walls
-Visceral layer: The inner layer that covers many of the abdominal organs
function of the mesenteries
attaches the digestive organs in the abdomen to the abdominal wall
organs the major mesenteries are connected
-small and large intestines
-spleen
-liver
-pancreas
layers in the intestinal tract
-Mucosa.
-Submucosa.
-Muscular layer.
-Serous layer or serosa
proper function of the intestinal tract
-absorb water via osmosis
-absorb electrolytes(active transport)
-absorb digestive enzyme
-produce&absorb vitamins
-form feces
organization of a tooth
-crown=emergent part, enamel outer layer
-neck
-root=embedded in socket, has dentin:mineralized matrix similar to bone, pulp cavity: neurovascular core
roles of the four tooth types
1)Incisors=cutting&nipping
2)Cuspids=tearing&piercing
3)Bicuspids=grinding&crushing
4)molars=grinding&crushing
deciduous teeth(primary)
-baby teeth
babys have how many teeth
20 teeth
-2 incisors
-1 canine
-2 molar
(per side per jaw)
adults have how many teeth?
32 teeth
-2 incisors
-1 canine
-2 premolar
-3 molar
per side per jaw
organization of a gastric pit?
indentations in the stomach which denote entrances to the tubular shaped gastric glands
What are the roles of mucous epithelium
-Lubrication
-protection
-digestion and absorption of food nutrients
What are the roles of parietal cell
-type of gastric gland
-produce HCl
-keeps stomach ph acid to kill microorganisms, denatures proteins in food, breaks down cell walls&connective tissue
-activates pepsin
What are the roles of chief cells
-type of gastric gland
-secretes pepsinogen
-acid(HCl) concerts pepsinogen to pepsin(a protease)
-produce rennin and gastric lipase
What are the roles of G cells?
-type of gastric gland
-secretes gastrin hormone:increases the activity of parietal&chief cells& gastric mixing
What does the pancreas contribute to digestion?
-exocrine acinar cells secretes pancreatic juice
hepatic portal system
-receives oxygenated blood via hepatic artery and deoxygenated blood goes back to the heart via the hepatic vein
-blood from digestive tract goes to the liver via hepatic portal vein
-then drain into hepatic vein
liver in the overall circulation of blood
-receives a dual blood supply from the hepatic artery and portal vein
Where is bile produced?
liver
Where is bile stored?
gallbladder
presence of bacteria in the large intestine a good thing?
supplying essential nutrients, synthesizing vitamin K, aiding in the digestion of cellulose, and promoting angiogenesis and enteric nerve function
carbohydrates and role with digestive process?
-amylase digests carbs
-microvillibrush border hydrolyze
-lactase decline during adolescence=lactose intolerance
-contransport w/Na+ actively pumped into lumen to build concentration gradient
lipids and role with digestive process?
lipase digest lipid to fatty acids&monoglycerides
-bile salts assist via emulsification
-chylomicrons enter the lacteal via exocytosis form the intestinal cells
proteins and role with digestive process?
-pepsin in stomach digests protein into polypeptides
-pancreatic enzymes break down polypeptides to pepties&amino acids
-amino acids transported via facilitated diffusion
nucleic acids and role with digestive process?
-pancreatic nucleases hydrolyze polynucleotides to monomers
-brush border enzymes hydrolyze monomers to free nitrogen bases
-absorbed by active transport
mechanical digestion
physical breaking of food
propulsion
movement of food along the digestive tract via swallowing & peristalsis
chemical digestion
catabolic breakdown of food via enzymes
absorption
transport of nutrients from digestive tract into the blood
defecation
elimination of indigestible materials as feces
Buffers
-elevates pH of chyme to basic
-in pancreatic juice
Protease
-breaks down protein to plypeptides or amino acids
-in pancreatic juice
pancreatic amylase
-breaks down carbohydrates to disaccharides
-in pancreatic juice
nuclease
-digets DNA&RNA to nucleic acids
-in pancreatic juice
pancreatic lipase
-breaks down lipid to fatty acids&glycerol
-in pancreatic juice
in rectum
-internal anal sphincter:maintains resting anal pressure, involuntary control
-external anal sphincter: formed by skeletal muscle, voluntary control
1)cephalic phase
-regulation: stomach
-stomach prepares for food
2)Gastric phase
-regulation:stomach
-swallowed food activates gastric activity
3)Intestinal phase
-regulation:stomach
-food enter the upper portions of the small intestine
