DIGESTIVE TRACT Flashcards
WHAT IS THE MESSENTARIES
-prevent digestive tract from twisting on itself and provide passway for blood vessels and nerves
MUCOSA
-lines mouth to anus
-secrete mucus
-absorb
-protect
LAMINA PROPRIA
-nourish epithelium and absorb digested nutrients
-part of MALT
BLOOD SUPPLY
-splanchnic circulation
WHAT IS PARACRINE SIGNALING?
-a form of cell to cell communication
-cells produces signal to induce behaviour change in cell
WHAT DOES STOMACH ACID DO?
-activates pepsin and lingual lipase
-breaks up connective tissues
-converts ferric ions to ferrous ions
-destroys ingested pathogens
AMYLASE ALLOWS US TO DIGEST
CARBOHYDRATES
WHAT IS ANKYLOGLOSSIA?
-children born with short frenulum
-known as “tongue tied”
-can cause speech troubles
-solved by snipping frenulum
MECHANICAL DIGESTION
-physical breakdown of food into smaller particles
-can include emulsification of fats in S.I
CHEMICAL DIGESTION
-undergo hydrolysis reaction
-break down complex macromolecules
-uses enzymes
MUCOSAL BARRIER
-stomachs protection for acidity of gastric juices
-consists of:
1. bicarbonate rich mucus
2. tight junctions
3. damaged cells are shed quickly
WHERE DOES FAT ABSORPTION PRIMARILY OCCUR?
SMALL INTESTINE BY PANCREATIC LIPASES
INTRINSIC FACTOR
-only function of the stomach that is essential to life is the secretion of this
-required for absorption of B12 to produce mature erythrocytes
-without this pernicious anemia occurs
PERNICIOUS ANEMIA
-decrease in B12 = decrease in EMF = pernicious amenia
-also caused by immuno disorder that attacks the paritel cells
ROLE OF BILE IN SMALL INTESTINE
-break down fats
-nutrient absorption
-waste elimination
-feces color
MALT
-called Peyer’s Patches
-located in lamina propria
HIGH FAT EFFECT IN S.I
-bile produced in liver is secreted into S.I to digest fats and absorb fatty acids
PROTEINS ARE BROKEN DOWN INTO…
- large polypeptides
- small polypeptides and peptides
- finally into amino acids into capillaries
WHERE DOES PROTEIN DIGESTION BEGIN?
-in the stomach at low PH to convert pepsinogen into pepsin
WHY IS LIPID DIGESTION MORE DIFFICULT
-THEY ARE HYDROPHOBIC
BILE SALTS
-coat fat droplets and increase SA for emulsification by pancreatic lipases
WHERE DOES CHEMICAL DIGESTION OF LIPIDS BEGIN?
MOUTH
