T5: Digestive System

Question 1

5 stages of digestion

Answer 1

ingestion 
digestion
absoprtion 
compaction 
defacation

Question 2

what is digestive tract/alimentary canal

Answer 2

mouth > anus

Question 3

GI tract

Answer 3

stomach + intestine

Question 4

what is mechanical digestion p

Answer 4

physical digestion

Question 5

what is chemical digestion

Answer 5

enzyme breakdown

Question 6

3 basic layers of gut

Answer 6

mucosa (epithelium , lamina propria, muscular mucosa)
submucosa (loose CT
Muscularis externia (2 smooth muscle layers= inner circular, outer longitudinal)

Question 7

2 mechanisms that move food

Answer 7

peristalsis - waves of contraction

segmentation- alternate constriction

Question 8

2 peritoneum layers

Answer 8

1. parietal perl (on walls)

2. visceral peri (on organs)

Question 9

role of mesentaries

Answer 9

allows organ movement

passage for BV, nerve, LV

Question 10

explain parasympathetic control of digestive

Answer 10

cranio-sacral

• vagus nerve+ sacral spinal cord
• increase secretion and motility

Question 11

explain sympathetic control of digestive

Answer 11

thoracic-lumbar

• thoracic and upper lumbar spinal cord
• decrease secretion and motility

Question 12

what does myenteric plexus do

Answer 12

b/w 2 musclurus externa layer

- frequencies and strength of contraction

Question 13

what does submucosa plexus do

Answer 13

glandular sectrions

Question 14

what is oral cavity (buccal) lined with

Answer 14

• stratified squamous

- keratoinzed if food abraisens

Question 15

what does food stimulating oral receptors do

Answer 15

trigger involuntary chewing reflex

Question 16

what is mastication and what does it allow

Answer 16

chewing= mech digestion

• easy to swallow
• SA for enzymes

Question 17

determine if herbi or carni

Answer 17

herb= teeth come together at same time

flatter teeth

Question 18

two types of salivary gland

Answer 18

intrinsic

extrinsic

Question 19

3 types of intrinsic saliva glands and their function

Answer 19

lingual
labial
buccal
- lingual lipase, saliva

Question 20

3 types of extrinsic saliva glands and their function

Answer 20

parotid
submandibular
sublingual

Question 21

PNS response to salivary glands

Answer 21

facial + glosso

= thin, enzyme rich saliva

Question 22

SNS response to salivary glands

Answer 22

superior cervicle ganglion

= less, thicker, saliva

Question 23

3 things saliva contains

Answer 23

salivary amylase
linguil lipase
mucus

Question 24

summarise digestion in oral cavity

Answer 24

mechanical 
salivary amylase (polysaccharides > oli_|)
lingual lipase (fat digestion)

Question 25

pharyngeal constrictor muscles

Answer 25

force food down when swallowing

Question 26

2 phases of swallowing

Answer 26

``` buccal phase (voluntary) pharyngoesphageal phase (invol) ```

Question 27

what prevents food from coming back into mouth

Answer 27

tongue against hard palate pharyngeal constrictor muscles epiglottis close

Question 28

what is peristalsis controlled by

Answer 28

myenteric plexus

Question 29

change in tissue from gastro-oesophageal junction

Answer 29

stratified squamous > simple columnar

Question 30

rugae

Answer 30

folds outside stomach= flatten when full

Question 31

whats different about muscular external in stomach

Answer 31

3 layers= inner oblique muscle (mechanical digestion)

Question 32

what splinter is b/w stomach and duo

Answer 32

pyloric

Question 33

whys there tight junction b/w simple columnar of stomach

Answer 33

prevents gastric juice from digestion lamina propria

Question 34

4 types of cell in stomach

Answer 34

mucous: secrete mucos + resist acid stem= continual new cells parietal= HCL + intrinsic chief cells= pepsinogen + gastric lipase

Question 35

what is a zymogen and example in stomach

Answer 35

digestive enzyme thats a inactive protein | pepsinogen

Question 36

pepsinogen to pepsin

Answer 36

parietal cells HCL removes amino acid = pepsin

Question 37

summery digestion in stomach

Answer 37

mechanical (churning) pepsin (>peptide chains) gastric + lingual lipase (fat digestion

Question 38

what happens in duodenum (4)

Answer 38

- stomach acid nutrilsed by bicarbonate form pancreas - pepsin inactivated with higher pH - bile acids emulsify fats - chemical digestion by pancreatic enzymes

Question 39

ileocecal valve

Answer 39

regulated passage into large intestine

Question 40

what does liver do

Answer 40

secrete bile = emulsify fats

Question 41

what artery supplies most of SI and half large

Answer 41

superior mesenteric artery

Question 42

pancreatic enzymes

Answer 42

panc. lipase panc. amylase nuclease

Question 43

what does plicae circulates do

Answer 43

increase contact wiht mucosa slow passes\age mixing

Question 44

complete digestion of carbohydrates

Answer 44

- salivary amylase (starch olosaccharides) - pancreatic amylase (starch disaccharides) - brush border enzymes (monosaccharides) > cappilaries

Question 45

complete digestion of protein

Answer 45

pepsin (stomach) pancreatic protease (polypep > olipep_ brush border (peptides > amino ) > capilaries

Question 46

complete digestion of fat

Answer 46

lingual + gastric lipase bile and agitation= emulsification pancreatic lipase lipase (tryglceride > 2 fatty and mono) micelles in bile - transport + diffuse into epithelium - packaged into secretory vesicles > lacteal)

Question 47

tissue of large intestine

Answer 47

simple columnar + goblet (librication_

Question 48

internal vs external anal sphincter

Answer 48

``` inter= smooth ext= skeletal ```

Question 49

neural control of defection

Answer 49

``` intrinsic defecation reflex (myenteric plexus= stretch receptors para defection reflex (rely of internal spin) voluntary control (extern spin) ```