digestive system

Question 1

GI tract

Answer 1

break down large molecules to small ones that be absorbed by the bodys cells

Question 2

GI tract tissue layers

Answer 2

mucosa, submucosa, muscularis externa, serosa

Question 3

mucosa

Answer 3

epithelium tissue, lines lumen, secrete digestive enzymes

Question 4

submucosa

Answer 4

loose connective tissue, contains blood vessel and lymph nodes

Question 5

muscularis externa

Answer 5

double layer of smooth tissue

Question 6

serosa

Answer 6

squamous epithelium, secretes serous fluid

Question 7

chemical digestion

Answer 7

1) hydrochloric acid 2)bile salts 3)specific enzymes, salivary glands secrete saliva

Question 8

motility - peristalsis

Answer 8

enteric nervous system leads to contraction and relaxation of smooth muscle producing waves of contraction called peristalsis

Question 9

fat digestion in stomach

Answer 9

acidic lipase optimum ph is 3-6. adults acidic lipases are responsible for 30% of lipid hydroylsis

Question 10

pyloric sphincter

Answer 10

the gate of the small intestine opens and allows limited amount of chyme to pass

Question 11

small intestine - major chemical digestion

Answer 11

duodenum - digestion , ileum - reabsorption

Question 12

villi, microvilli

Answer 12

increase surface area, microvilli also produces brush border enzymes

Question 13

zymogens

Answer 13

digestive enzymes inactive form, these zymogens are converted to active form by brushborder enzymes

Question 14

trypsinogen ( brushbe)

Answer 14

activated enteropeptidase to produce trypsin, found in the intestinal mucosa

Question 15

absorption of AA and small sugars

Answer 15

require energy to be absorbed - active transport, once in epithelium cells they move by facilated diffusion into blood

Question 16

absorption lipids

Answer 16

short chained fatty acids - directly into bloodstream. chylomicrons pass into lymphatic capillaries and transport dietary lipods to body tissue

Question 17

absorption of water, vit and minerals

Answer 17

water is passive and driven osmotic gradient. vit absorption hydrophobic fat soluble ADEK, hydrophilic water soluble BC