2.3 Digestive System Liver, Pancreas Gallbladder Flashcards Preview

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Flashcards in 2.3 Digestive System Liver, Pancreas Gallbladder Deck (150):
0

9 main areas of digestive system and function?

Oral cavity - ingestion and initial fragmentation
Tongue and pharynx

1

Parakeritinsed epithelium?

Hard palate/masticatory mucosa.
Superficial cells not pyknotic nuclei.

What is pyknotic ? Irreversible condensation of chromatin.

2

names for parotid and submandibular gland ducts?

Stensens and whartons duct

3

4 types of tongue papillae?

Filiform, fungiform, circumvallate, foliate

4

How to differentiate between oesophagus and ureter?

Muscularis externa - oesophagus inner circular outer longitudinal. Ureter - opposite

5

Organs of GI tract and accessory organ

Mouth, isthmus of fauces, oesophagus, stomach, si, li, cecum, rectum

Teeth, tongue, salivary glands, liver, gallbladder, pancreas

6

Glands of GI tract?

Intraepithelial - goblet cells

Mural
Intra - tunica : mucosa, submucosa
Extra - major salivary glands, liver, pancreas

7

Functions of digestive system? (6)

Ingestion, swallowing
H+ secretion, digestive enzymes
Mixing and propulsion
Absorption
Reabsorption of water and undigested mat
Elimination of digested material - defecation

8

Oral cavity consists of?
What is the isthmus of fauces?

Cheeks, hard and soft palate, tongue
Space extends from gums + teeth

Fauces - opening between oral cavity + pharynx

9

Salivary glands (3)

Moist and clean oral cavity
Secretion of mucus increase - chemical digestion
3 pairs of glands

10

Frenulums - teeth?

Decidous - baby teeth, 6months, 20 by 2 years, fall out by 2-6 years

Permanent - 32 total, 3rd set of molars by end of adolecense (Widom teeth)

11

Tongue structure, extra (2)

Mostly muscular -
grip + reposition food
Swallowing
Speech

Taste buds - circumvallate, foliate, fungiform, filiform papillae
Lingual tonsils

12

What is the isthmus of fauces?

.

13

Pharynx (3)

Naso - respiratory

Oral - digestive and respiratory

Laryngo - digestive and respiratory

14

Opening of laryngopharynx regulated by

Epiglottis -> elastic cartilage - 9th cartilage of larynx

15

What are the different phases of swallowing?

.

16

Structure of pharynx ?
Muscular and adventitia

Pseudostratified ciliated
Oro+laryngopharnx -> ssnk

Striated skeletal muscle
Adventitia external to muscle

17

What are the pharyngeal aponeurosis?

Fibroelastic ct -> muscle insertion

18

Muscle of pharynx(3)
Innervation

Constrictor muscles
Sup, mid, inf
Squeeze bolus -> into esophagus
Vagus nerve

19

Esophagus (5)

Food swallow -> folding longitudinal of lumen
C6-T10
25cm length
Behind trachea
Passes thru oesophageal hiatus (diaphragm) -> enter abdomen

20

4 constrictions of esophagus?
4 parts and length?

Cricoid, aortic, bronchial, diaphragmatic

Cervical 4-5, mediastinic 16, diaphagmatic 1-2, abdominal 3

21

GI Tract - general structure 4
Describe first 2 and how increase SA of first?

Mucosa, submucosa, muscularis externa, serosa
Mucosa - epithelium, lamina propria (MALT LCT with capillaries)
Muscularis mucosa - thin layer of sm cells - local movements
Submucosa - CT - minor blood+lymph vessels , nerves - elastic fibres - regain shape

Plicae, microvilli, villi, glands/crypts

22

Last 2 layers of GI tract?
And innervation of muscularis externa

Muscularis externa - 2 layers of SM - peristalsis, segmentation
Inner circular - squeezes, formation of sphincters
Outer longitudinal - shortens gut

Myenteric plexus between ME.

23

Submucosal plexus of gi tract?

Meissner plexus -> control gland, sensory function, contraction of MM

24

Structure of esophagus?

Mucosa - ss non keratinised, lp, mm
Submucosa – seromucous glands
Muscularis externa - inner and outer
In thirds : sup - skeletal. Mid - sm and skeletal. Inf - only sm

Adventitia - CT, no serosa

25

Esophagus - seromucous glands?

Secrete thin layer of mucus - lubrication
Esophageal cardiac glands - tubular - only LP - terminal part of oesophagus - neutral mucous

26

Muscosa and submucosa form?

Longitudinal folds -> stellate aspect of lumen disappears when swallowing. Reappears -> elastic recoil

27

Muscularis mucosa where evident in esophagus?
Submucosa contain.,

2nd and 3rd part

Elastic fibres, venous plexuses, drain into venous + hepatic portal circulation

28

Gastro-oesophageal junction (3)

Z line
Abrupt transition
Ss - epithelium - secretory mucosa (simple columnar)

29

2 sphincters of eosophagus?

UES - sup - cricopharyngeal sphincter - mech of swallowing + prevent air entrance

LES - inf - prevent reflux of acid into esophagus

30

What is reflux esophagitis?

Ulceration, difficulty swallowing (caudal stratified - replaced by columnar - lose resistance

31

Development defect of diaphram?

Hernia hiatus - herniation of abdominal portion of oesophagus

32

Abdomen surgical ares?

Left and right:
Hypochrondium
Lumber
Iliac fossa

In the centre : epigastric, umbilical, hypogastric

33

Example of retroperitoneal and extra peritoneal organs!

Pancreas, kidney

34

Duodenum and post abdominal wall?

Not completely surround by peritoneum

35

Abdominal aorta splits into

Celiac ( gastric, common hepatic, gastrodudenal )
sup - (ascending and transverse colon 2/3)
inf mesenteric artery - 1/3 transverse, descending, sigmoid
Renal - 20% of cardiac output
Adrenal

36

Infra and supra mesocolic space ?

.

37

Does retroperitoneal have a mesentery?
Lesser omentum is surrounded by?
Greater omentum?

No
Surrouded by peritoneum
Formation of other cavities

38

Stomach ?
Pyloric sphincter function

1.5L, EPIGASTRIC REGION - hypogastric
Greater and lesser curvature - ligaments attached - stomach and liver (lesser omentum)
Angular incisor, cardiac notch, fundus, body, pyloric antrum and canal
Regulation mat from stomach to duodenum

39

crypts of lieberkaun?

Found in SI
Brunenrs gland found in duodenum (submucosa)
Ileum - peyers patched

40

You need to learn about the stomach?

Posture, wispdth, position of other vicera, extent of filling effect, shape of stomach

41

Stomach position?

Inferior to diaphram, under liver

42

What forms the lesser omentum!

Hepatogastirc and hepatoduodenal ligament-
Bv reach liver
Portal vein
Hepatic artery
Extra hepatic billiary duct inserted onto ligament

43

Quick fact about greater omentum?

Behind - adipose tissue

44

Muscularis externa of stomach?

3 layers - oblique, circular, longitudinal.

Mechanical contraction - muscles contract
Mixing of digestive enzymes and proteolytic enzymes

45

Stomach mucosa epithelium?

Simple columnar, surface mucous cells.
Produce mucous -> protect stomach from acidic content
No absorption - except h2o, salts, lipids, drugs, alcohol

46

Effect of drugs and alcohol on stomach?

Damage mucosa of stomach,
Prostaglandins released
Loss protective function of mucosa

47

What level are the greater and lessor curvatures of the stomach located?

Level of the body

48

What angle antrum and body of stomach?
Pylorus and duodenum connected via?
What is at the surface of the internal wall of stomach? Where/when is this less prominent

90
Pyloric sphincter
Rugae, less prominent middle area + when stomach fills

49

Vascularisation of stomach?

Celiac trunk - l-r gastric artery; l-r gastro-omental artery

Veins parallel to artery, drained into hepatic portal vein

50

What supplies the fundus and body of stomach? Vascular

Upper gastric arteries

51

Gastric folds?

Longitudinal - distensibility

52

What are mammiliated areas in stomach?

Aeroles - delimited by permanent sulca

53

Where are glands of stomach located? What type? Name? Secretion? Cells in glands? Purpose?

Lamina propria,
Tubular, single, branched
body, fundus, cardiac, pylorus,
Mucous secretion -> protection against high acid level of stomach

54

How to differentiate between stomach and colon?

Lamina propria - stomach glands

Colon - mucous secreting cells + intercalated between are enterocytes

55

Submucosa, muscularis, serosa of stomach?

Submucosa - little
Muscularis externa - internal :oblique, circ, longi
Serosa - peritoneum

56

Defensive forces in the stomach? (6)

Surface mucosa, bicarbonate, mucosal blood flow, membrane transport, epithelium regenerative capacity, elaboration of prostaglandins

57

Injury of stomach leads to?

Ischemia, shock, delayed gastric emptying

58

3 types of stomach glands and where found?

Cardiac - simple compound tubular, mucous secreting - cardiac region, surround esophageal orifice

Pyloric - tubular branched coiled mucous + gastric secretion - pyloric antrum

Gastric/fundic - simple tubular branched at base - thruout stomach except above areas. Long lifespan of cells - Pariental cells 200days

59

Gastric mucosa - gastric glands. Cells, tubularvesicular system

Pariental(150-200days) - hcl and intrinsic factor (b12 vit absorption -> rbc production) -> tubulovesicular system -> proton pump, maintain acidic ph of stomach. Large no. Of mito.
Chief (60-90days) - pepsinogen (zymogen granules) + hcl -> pepsin
Neuroendocrine cells -gastrin
Surface/neck mucous cells

Pariental cells - larger - bud from lining epithelium, darker well stained compared to chief cells

60

Stomach glands -> Fundic mucosa, -3 levels and what cells located within

Surface neck cells - mucous cloudy production - level of lining epithelium + gastric pit
Neck cells - soluble clear secretion

Gastric pit(surface mucous cells) - isthmus (stem cells located, pariental, mucous neck) - fundus (chief and enteroendocrine cells)

61

Enteroendocrine cells (g cells)

Hcl
Gastric motility
Growth of epithelial cells
Open (chemoreceptors) and closed.

62

Gastrin, ghrelin, cck, secretin, gip, motilin. Where synthesised, stim and inhibit what?

Gastrin - g cells stomach - gastric acid - nothing
Ghrelin-cells in stomach-gh secretion-lipid met+fat usage in adipose
Cck - i cells duo+jujenum- gallbladder contraction,same as secretin-gastric emptying
Secretin - s cells duodenum - pancreatic enzyme, bicarbonate, growth- inhibit gastric acid secretion
Gip - k cells duo + jujenum - insulin released - gastric acid secretion
Motilin - m cells duodenum + jujenum - gastric+intestinal motility - nothing

63

Zollinger ellison syndrome?

Gastrinomas -> gastric + duodenal ulcers - damage of mucosa

64

2 types of neuroendocrine cells?

Open - cytoplasmic prolongement exposed to lumen - chemoreceptors

Closed - not reach lumen

65

Gastric serosa continuous with?

Parietal peritoneum of abdominal cavity via greater omentum

Visceral peritoneum of liver - lesser omentum

66

Small intestine - mesenteric arteries

Jej and ileum

67

Duodenum length and 2 extras

25cm - different structure and relationship to peritoneum

68

Si Function of enterocytes ->

Enterokinase - trypsinogen -> trypsin

Trypsin : pancreatic zymogens (inactive proenzymes) ->active enzymes
Eg pro:elastase, carboxypeptidase, phospholipase -> without pro.
Chymotrypsinogen -> trypsinogen

69

SI (4)

Continues digestive process started in stomach
Absorbs food and water
Food exiting stomach : chyme -> chymus
Chymus exposed to pancreatic and biliary secretion -> chyle

70

Pancrease and duodenum.
Wall of intestine?

Exocrine pancreas secrete into duodenum
Wall of intestine - lacteal + bv

71

SI Macroscopic and microscopic devices

Plicae, villi, crypts and glands, microvilli

72

Si where are plicae most numerous?
And plicae points

Distal - duo
Beginning of jej
Perm tranverse folds - cont core of submucosa

73

Biochemical devices of si digestion

Luminal - pancreatic enzymes and bile
Membrane - enzymes of microvilli (glycocalyx)

74

Mechanical devices of si?

Contraction and relax of intestinal wall (muscularis externa - cl)

75

Duodenum?

25cm, first, shirtest and widest part.
Bulbis duodenalis, descending, horizontal, ascending portion
C shaped.
Retroperitoneal except bulbos duodenalis

76

Sup mesenteric artery and veins drain into?

Portal vein

77

SI Explain bile, pancreatic enzymes, major-minor papillary duct?

Bile - emulsify lipids
Pancreatic enzymes - proteases, amylases, lipases, nucleases
Minor pap - accessory pancreatic duct

Major pap - main pancreatic duct + coleducus -> sphincter of oddi.

78

What stimulates opening/closing of the sphincter of oddi?

CCK

79

Si mesenterial part

Jej(2.5m) ileum(3.5m) - surrounded by peritoneum.

80

Root of mesentary

Length 15cm
Aterial arcade - longer in jej, shorter in ileum
Vasa recta - jej few large loops, ileum greater no. Of loops
Nerves
And bv from sup mesenteric artery

81

Structure of SI summary

Mucosa - simple cuboidal epi, villi, tubular glands/crypts, muscularis mucosa(2layers), lamina propria (galt)
Submucosa - duo(brunner glands) - acidic secretion - compound tubular
Muscularis externa - CL
Serosa

82

si villi cross-section

Lamina propria - lacteal, vascular, immune cells
Sm cells extending from muscularis mucosa into core of villus
Loost ct, cappillaries, lymphatic vessels (lipid absorption)

83

Si - crypts of lieberkaun

Paneth cells - defensins + lysozymes. Basally located

84

5 cells types found in intestinal mucosal epithelium

Enterocytes - primary function - absorption
Goblet cells - mucous secretion
Paneth cells - defensins and lysozomes
Enteroendocrine cells - paracrine and endocrine hormones
M cells (microfold cells) - modified enterocytes cover lymph nodules in lamina propria

85

Si- Enterocytes ?

Simple columnar - line mucosa
glycocalyx - important enzymes - digestion
Digestion of sugars(di+oligo-saccharides-> mono), proteins (peptidases + brush border)

86

What is the first enzyme involved in digestion
.

Pepsin

87

Si - bile

Convert lipids - smaller molecules -> into lacteal vessels

88

Si - stem cells for renewal -

3/5 days - enterocytes+ mucous cells
4 weeks - paneth+enteroendocrine cells

89

Ileum (4)

Peyers patches - galt (higher no. In ileum) - mucosa lamina propria / sometimes submucosa
Dome b cells
Germinal centre (b and t cells, apc)
Follicle associated epithelium (m cells(dendritic cells) - take up antigen)

However galt/lymphoid tissue found thruout digestive system

90

Lamina propria of villus of illeum

Plasma cells, eosinophils, macrophages, mast cells
Sm, bv,lv

What does sm do? Connects villus to muscularis mucosae

91

What is inflammatory bowel disese

Crypts knvaded by inflammatory cells - chronic granulomas -> destroy musuclaris mucosae -> fibrosis - replaced by CT (collagen)

92

Distinguish duodenum, jej, ileum

Duo - submucosa - brunner glands. Leaf life villi.

Ileum - peyers patches

D->I increase in goblet cells

93

2 types of motility?

Segmentation - non-coordinate sm contraction
Peristalsis - co-ordinated

94

Brunenr glands?

Mixed tubular submucosal, duodenum,
Zymogen + mucus secreting.

Alkaline -> protect proximal si from stomach acid

95

Si, epithelial cell renewal?

Stem cells from base of intestinal gland

96

LI length, portions and relaitons to peritoneum, function, structures

1.5-1.8m.
Cecum + vermiform appendix
1 Ascending 15cm
2 Transverse 50cm
3 Descending 25cm
4 Sigmoid
Rectum
Anal canal
1-3 not covered by peritoneum
2-4 connect to post wall of abdominal wall by mesenteries -> visceral peritoneum - form double layer

97

Three distinct features of LI?

Teniae coli - 3 narrow bands outer longitudinal layer of externa. Absent in rectum, anal canal, vermiform appendix
Haustra coli - sacculatiojs between external surface of cecum and colon
Omental appendices - fatty projections of serosa on outer surface

98

Function of LI

Reabsorption of electrolytes and water,
Elimination of undigested food and waste - propulsion - rectum

99

Columnar to goblet cell ratio in LI.
TOWARDS RECTum the ratio is?

4:1
1:1 goblet cell increases

100

LI epithelial cell turnover

Similar to SI

101

Vascularisation of LI

Sup, inf mesenteric arteries
Splenic and sup mesenteric vein -> form hepatic portal vein - drain mesentery of sigmoid colon (intra peritoneal) - connected to post wall of abdomen .

102

Inner wall of LI (3)

Sulci - semilunar plicae
Due to tonic contraction of ext longitudinal layer
No plicae or villi

103

Structure of LI

Mucosa - no villi, plicae. Smooth surface, crypts of lieberkaun(straight tubular) extend thruout. Simple columnar.
Lamina propria - collagen table(collagen and proteoglycans between basal lamina and epithelial cells), pericryptal fibroblast sheath(may differentiate into macrophage), galt, lymphatic vessels(muscularis mucosae)

Submucosa - similar to rest of gi tract
Muscularis - CL
Serosa - peritoneum

Goblet cells more numerous in LI than SI

104

How to distinguish stomach and colon?

Lining epithelium - stomach only mucous secreting cells form mucous membrane. Whereas LI other cells present

105

Hirshsprings disease

Congential megacolon - dilation - consitpation
Neural crest cell migration failure - abnormal innervation of bowel

106

Aooendix contain?

Lymphatic follicles in mucosa. Extend into submucosa.
Thick circular layer. Thin outer longi layer.
Serosa continuous with mesentery of appendix

107

Rectum length and extra point!
Anal canal length and 4

15cm - lacks haustra

Anal canal - tenai dilated in ampulla of anal canal - communicates with anus by sphincter system - 3 zones,

108

Anal canal 3 zones and what glands

Colorectal - simple columnar
Anal transitional - ss epi. Also stratified columnar between transition of colorectal to ATZ
Squamous - ss epi

Anal glands - extend into submucosa + muscularis externa. Branches tubular straight mucous. Ducts lined with stratified columnar epi.

109

Also skin surrounding anl orifice!

Large apocrine glands - circumanal glands.
Maybe sexual attractant.
Hair follicles and sebacous glands found at this site

110

Internal and external sphincter?

Int - sm - involuntary

Ext - skeletal - voluntary contraction

111

Anal folds, valves and sinuses

8-10 longitudinal folds
Valves - small horizontal plicae at base of folds
Anal sinuses - behind valves - where glands open

Pectinate line - determined by valves

112

Deep to anal columns there are?
Protrusions int and ext

Av anastomoses. If vascular plexa protrude - int/ext -> int/ext hemmoroids - bleeding

113

Major salivary glands

Extra mural glands
Parotid - tubuloacinar - duct of steno - into upper cavity of molar teeth
Sublingual - mixed tubuloacinar
Submandibular - mixed tubuloacinar

114

Liver exocrine and endocrine function?

Exo - Bile secretion - emulsify fatty acid -> droplets -> absorbed in SI

Endo - synthesis of proteins - albumins, globulins etc

115

Liver 6 main functions

Fat met - ox of troglycerides. Synthesis of plasma lipoproteins. Synthesis of cholesterol
Carb met - convert carbs and proteins into fatty acids + triglycerides. Regulation of blood glucose conc (glycogenesis, glycogenolysis, gluconeogenesis)
Protein met - syn plasma proteins, non essential aa, detox of waste products (deamination of urine)
Glycogen storage
Detox of drugs and toxins - eg alcohol
Secretion of bile

116

Liver protein met -> plasma proteins examples

albumins, globulins, clotting factors

117

Liver where is visceral peritoneum not present?

Bare area where liver adhere/connects to other organs

118

Lesser omentum and liver?

Connects stomach, duodenum and liver

119

Post margin of liver?

Veins draining into vena cava

120

Liver: shape, weight, lobes, ligaments

Kidney shaped. 1.5kg. 4 lobes - left right caudate quadrate.
Falciform, coronary, triangular, round ligament

121

Falciform ligament

Connects diaphragmatic face of liver to diaphram -> only see ligaments and 2 lobes

122

Ligament venosu , round ligament

Residue of embryonic blood vessels,

123

Emrbyonic development of liver?

Endodermal evagination wall of foregut
Hepatic diverticulum - proliferates - hepatocytes (cords)
Original stalk of diverticulum -> common bile duct.
Outgrowth from common bile duct - gallbladder and cystic duct

124

H zone of liver

2 longitudinal and 1 transverse sulci - specific structures
2 extra lobes seen - only seen inferiorly.

125

Post face of liver

Hepatic veins -> inf vena cava
Triangular ligament -> obtained by fusion of 2 peritoneum layers (bare area of liver)
Corinary ligament surround bare area

126

How many segments in liver?

8 based on distribution of bile ducts and hepatic vessels

127

Liver vascularisation

Proper hepatic
Inf mesenteric vein -> splenic vein + sup mesenteric -> hepatic portal vein

128

Liver structure

Glisson capsule - parenchymal organ. Sinusoids, hepatic lobules. Central vein

Portal triad : at corner of hexagonal lobules. (Bile duct, art, portal vein.)

129

Portal triad

Art, vein, bile duct. Canal of herring,
Cholangiocytes (undifferentiated) - epithelial cells, line biliary tree. Primary cilium - detect luminal flow. Initially cuboidal. Increase in duct diameter -> columnar

Bile flow in opposite direction to blood flow (to central vein)

130

Classic lobule venous

Central vein (terminal hepatic venule) -> sublobular vein-> hepatic portal vein -> inf vena cav

131

Liver - portal triad - small ducts

Fuse form large duct - common hepatic duct - ultimately empty major papillae in duodenum

132

Liver - cappilaries

Mixed blood from liver and blood from digestive system

133

Liver - Different faces of classic lobule

Biliary face - adjacent to neighbouring hepatocyte - small depression on pm - canaliculi - bile produced - released

Vascular face - faces wall of capillary - sinusoid.

134

Liver - space between sinusoid and hepatocyte

Space of disse (0.2-0.5um)
Cells of ito (hepatic stellate cells/fat storing)
Store vit A.
Pathological condition - aSMA expressed - fibroblast prolongement - release collagen- fibrosis - myofibroblast - express specific marker

Wall of sinusoid - kupffer cell

135

Liver regen
Aged liver

Cells quintescent. Remove liver portion, cells activated - mitosis proliferation

Aged liver - regen - able to be donor

136

Stroma of liver contain?

Reticular fibres - t3 collagen

137

Portal lobules

Triangular
Biliary ductule
Corners of triangle with central vein.
Central part of triangle - portal triad

138

Liver acinus
3 zones

Rappaporta - diamond shape. 2 opposite corner = central vein. Other 2 = portal triad
Zone :
1 most oxygenated - sensitive to bile duct occlusion
2 mediate oxy
3 least oxy - sensitive to necrosis and oxygen deprivation
Increase in o2 increase in met activity
Damage to liver - zone 3 most vulnerable and involved

139

Mod of kidney

Accumulation of collagen.
Renal fibrosis

140

Which stain for collagen?

Sirus red

141

Biliary tree intra and extra hepatic bile duct

Monitored flow of bile and content regulation by cholangiocytes
Canal of herring lined by hepatocytes and cholangiocytes (liver progenitor cells).

142

Difference between space of mall and canal of herring?

Not location.
Whether lined entirely by cholangiocytes or partially
Space of mall duct lined entirely by above

143

Intra/exta-hepatic bile duct

Intra - ductules to interlobular bile duct to L/R hepatic duct - common hepatic duct

Extra - bile to gallbladder and duodenum.

Ducts contain - tall columnar epithelium, layers similar to alimentary canal except no Musuclaris mucosa

144

Gallbladder structure and basic info

10cm. 40-60ml. Cystic duct. Concentration of bile. Mucosa with folds.
Attached to visceral surface of liver. Remove 90% of water from bile.
Simple columnar epithelium.

145

Gallbladder mucosa characteristic features 4

Numerous short apical microvilli
Junctional complexes between adjacent cells
Apical and basal cytoplasm - conc mito
Complex lateral plications

Mucous secreting glands present lamina propria near neck of organ.


146

Wall of gallbladder?
What are the deep invaginations of mucosa extending into epm.externa?

No submucosa and muscularis mucosa

Rokitansky-ashoff sinuses

147

Pancreas quick points!

L1 and l2 level
Retroperitoneal
2 ducts - main pancreatic duct and accessory pancreatic duct

148

What are sphinctors on ducts made of?

Smooth muscle

149

Function of exocrine pancreas?

Tubuloacinar compound serous
Function - synthesis+ secretion if lytic enzymes (zymogens) activated by trypsin