GI Flashcards
Chemical digestion
Changing food chemically so body can absorb by (enzymes, HCI, saliva)
Mechanical digestion
(Physical) break down of food to small particles (chewing,mashing..)
(key nutrients) Carbohydrates
Amylase (break down of starches and sugars) - glucose - absorbed by intestinal villi (starts in mouth)
(key nutrients) proteins
Pepsin (break down of protein) -amino acids -absorbed by intestinal villi (starts in stomach)
(key nutrients) fats
Bile (Liquifies fat) & lipase (dissolves fat)- fatty acids & glycerol - absorbed by lacteals
(Saliva glands) parotid
Front of ears (sour taste)
(Saliva glands) submandibular
Corners of jaw
(Saliva glands) sublingual
Under tongue
What is saliva made up of
Water (plasma), lysozyme (cleans mouth) and amylase (chemical breakdown of starches and sugars)
Cardiac sphincter / LES
Entrance of the stomach (closes to prevent GERG reflex)
Mechanical Digestion in stomach
Muscles in your stomach work together
Pyloric sphincter
Exit of stomach
Bolus
Ball of food (when it enters stomach)
Chyme
Semi liquid food (when it exits stomach)
(Gastric juices) HCL
Softens meat and kills bacteria
(Gastric juices) pepsin
Breaks down protein into amino acid
(Gastric juices) mucin
Coating of stomach lining to protect from HCL and pepsin
(Gastric juices) intrinsic factor
For stomach to absorb vit B12
-parietal cells (produce intrinsic factor)
(Small intestines) duodenum
1st part of small intestine (chemical digestion)
(Small intestines) jejunum
2nd part of small intestine (nutrient absorption)
(Small intestines) illeum
Last part of small intestine (vit B12 absorbed)
90% of digestion and absorption occur In the
Small intestines
Small intestinal villi
Increases absorption
Small intestinal villi (blood capillaries)
Absorb glucose and amino acids
Small intestinal villi ( lymph capillaries)
(Lacteals) absorb fatty acids, glycerol, vit A,D,E and K
Duodenum secretes
Secretin and CCK
Secretin
(Triggered by fat) stimulates the liver to PRODUCTION BILE
CCK
Stimulates gallbladder to RELEASE BILE and pancreatic secretions. Also relaxes sphincter of oddi
(Large intestines)
Cecum-ascending colon-hepatic flexure-transverse colon-splenic flexure-descending colon-sigmoid colon-rectum-anus
What does the large intestines do
Absorbs water, vitamin and electrolytes
-produces vit K
Defecation reflex
Stretches rectum- Signals spinal cord- sends back signal to internal anal sphincter relaxes
Bile
Liver-hepatic ducts-cyctic duct- gallbladder-cyctic duct- common bile duct-sphincter of oddi
Pancreatic enzymes
(Amylase, pepsin, lipase and bicarbonate (neutralizes HCL)
-pancreatic duct-common bile duct- sphincter of oddi
Livers clotting factors
Prothrombin- thrombin- fiberginergin-fibrin
Peristalsis
Wave like movements in smooth muscle
Histamine
Stimulates production of HCL
Gastrin
Stimulates production of gastric juices from Gcells
What does the liver do with excess cholesterol and bilirubin
Turns it into bile
The liver filters
Old RBCs and forms bilirubin. Also filters bacteria (detoxes harmful substances and medications) - then converts ammonia to urea
What does the liver activate
Vitamin D
Albumin
Maintains blood volume
Globulins
Carry fats
Lipoprotein
Transport fats
Liver stores
Iron, copper, Fats and vitamins
Carbohydrate metabolism
Excess glucose is stored as Glycogen (glycogenesis) then converted back to glucose
The liver manufactures
Cholesterol
