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Alimentary Physiology Flashcards

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1
Q

What are the 4 functions of the GIT?

A

digestion
absorption
secretion
motility

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2
Q

Where does the GIT start and end?

A

Beginning of the oesophagus to the end of the rectum

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3
Q

What are the 3 pairs of salivary glands called?

A

Parotid
Sublingual
Submandibular

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4
Q

Where are the parotid salivary glands located?

A

Anterior the ears

Either side of the mouth

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5
Q

Where do the sublingual glands secrete from?

A

Underneath the tongue

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6
Q

Where do the submandibular glands secrete from?

A

From underneath the jaw

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7
Q

Can the oesophagus work against gravity?

A

Yes

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8
Q

By what motility movement does food pass down the oesophagus?

A

Peristalsis

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9
Q

What is the primary role of the stomach?

A

Storage

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10
Q

Is the stomach an acidic or alkaline environment?

A

Acidic

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11
Q

What is the primary role of the pancreas?

A

To secrete enzymes and hormones

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12
Q

What is the functions of saliva?

A

To act as a lubricant when chewing and breaking down food

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13
Q

What is the function of the gallbladder?

A

Store and concentrates bile

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14
Q

How much bile can the gall bladder store?

A

up to 50ml

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15
Q

What colour is the gall bladder?

A

Green

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16
Q

What is the main function of the small intestine?

A

Nutrient absorption

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17
Q

What is the primary function of the large intestine?

A

Water absorption and the formation of faeces

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18
Q

What are the 4 layers of the tube wall of the GIT?

A

Mucosa
Submucosa
Muscularis Externa
Serosa/Adventitia

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19
Q

What are the 3 layers of the mucosa?

A

Epithelium
Lamina propria
muscularis mucosae

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20
Q

What is the change in epithelium from the mouth and oesophagus to the stomach, small and large intestine?

A

Mouth, oesophagus - stratified squamous epithelium

Stomach ect.. - simple columnar

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21
Q

Why does the epithelium differ along the GIT?

A

Differs for adaptation to function

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22
Q

What is the lamina propria composed of?

A

Loose connective tissue

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23
Q

What is the submucosa composed of?

A

Thick irregular connective tissue

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24
Q

What is the function of the submucosa?

A

To support the mucosa

Both psychically and with blood vessels ect..

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25
What is the submucosal plexus?
Extensive neuron network surrounding the submucosa
26
What is the muscularis externa composed of?
2 concentric thick layers of smooth muscle Inner circular Outer longitudinal
27
What is the inner layer of concentric muscle in the muscularis externa?
Circular muscle
28
What is the outer layer of concentric muscle in the muscularis externa?
Longitudinal muscle
29
What does the circular muscle control?
Lumen diameter
30
What does the longitudinal muscle control?
The length of the gut tube
31
What is the name of the neuron network in the muscularis externa?
Myenteric plexus
32
What is the myenteric plexus + submucosal plexus =?
Enteric nervous system
33
What is the difference between the serosa and the adventitia?
Adventitia - located outside the peritoneal cavity | Serosa- located within the peritoneal cavity
34
Which nerve transmits parasympathetic activity to the GIT?
Vagus nerve | CN X
35
From which cranial nerve does the vagus nerve originate?
Cranial nerve 10
36
Is the vagus nerve stimulatory or inhibitory of the digestive system?
Stimulatory - REST AND DIGEST
37
Which nerves innervate parasympathetic activity on salivation?
Facial and glossopharyngeal nerves
38
Which nerve transmits sympathetic activity to the GIT?
Splanchnic nerves
39
Is the sympathetic nervous system inhibitory or stimulatory of the GIT activity?
Inhibitory - FLIGHT OR FIGHT
40
What are the 3 main branches of the abdominal aorta that supply the GIT?
Celiac trunk Superior mesenteric artery Inferior mesenteric artery
41
Which part of the gut does the celiac trunk supply?
Foregut
42
Which part of the gut does the superior mesenteric artery supply?
Midgut
43
Which part of the gut does the inferior mesenteric artery supply?
Hindgut
44
Give examples of organs found in the foregut?
Stomach Pancreas Liver Gallbladder
45
Give examples of organs found in the midgut?
Small intestine Ascending colon Proximal 2/3 of transverse colon
46
Give examples of organs found in the hindgut
Descending colon Sigmoid colon Rectum Distal 1/3 transverse colon
47
Which veins drain the stomach?
Gastric veins
48
Which veins drains the pancreas?
Splenic vein
49
Which vein drains the midgut?
Superior mesenteric vein
50
Which vein drains the hindgut?
Inferior mesenteric vein
51
Where do the superior and inferior mesenteric vein drain into?
Hepatic portal vein
52
Where does the hepatic portal vein drain into?
Hepatic vein
53
Where does the hepatic vein drain into?
IVC
54
Which artery supplies the liver?
Hepatic artery
55
Which vein drains the liver?
Hepatic vein
56
Describe the blood in the hepatic artery
Oxygen rich | Nutrient deficient
57
Describe the blood in the hepatic vein
Oxygen deficient | Nutrient rich
58
What are the 3 principal dietary constituents?
Carbohydrates Proteins Fats
59
What are the 3 monosaccharides?
Glucose Galactose Fructose
60
What are the 3 disaccharides?
Lactose Sucrose Maltose
61
Which digestive enzyme breaks down lactose?
Lactase
62
Which digestive enzyme breaks down Maltose?
Maltase
63
Which digestive enzymes breaks down sucrose?
Sucrase
64
What is the plant storage form of glucose?
Starch
65
What the the animal storage of glucose?
Glycogen
66
Why can't our digestive enzymes break down cellulose?
Because we don't produce the enzyme cellulase
67
Where is cellulose broken down?
In the colon | By bacteria
68
Which enzyme breaks down starch and glycogen?
Alpha amylase
69
Which bonds link glucose monomers in starch and glycogen?
Alpha 1,4- glycosidic bonds
70
Which epithelium covers villi?
Columnar epithelium
71
What structure is the villi covered in?
Microvilli
72
Which is villi then covered in microvilli?
To increase surface area for absorption even further
73
Which membrane is on the outer surface of the vili?
Apical membrane
74
Which membrane is on the inner surface of the villi?
Basolateral membrane
75
What is meant by transcellular?
Going through the cell
76
What is meant by paracellular?
Can pass between the cells as they are not entirely tight
77
How many proteins are needed to transport molecules through a cell?
At least 2 One to get in One to get back out
78
To which ion is glucose transport coupled up to?
Sodium
79
Through which protein is glucose transported?
GLUT 2
80
Which transporter transports fructose into the cell?
GLUT 5
81
Which transporter transports fructose back out of the cell?
GLUT 2
82
What are proteins polymers of?
Amino acids
83
Which bond links amino acids to form proteins?
Peptide bonds
84
Give an example of a post-translational modification in a protein
the addition of carbohydrate | the addition of a phosphate
85
Enzymes which hydrolyse peptide bonds are known as what?
Proteases | or Peptidases
86
Where do endopetidases act on?
The inside of the protein
87
Where do ectopeptidases act on?
On the terminal amino acids of the protein
88
What are the 2 reactions involved in the formation and breakdown of proteins?
Hydrolisation | Condensation
89
What are most ingested fats in the form of?
TAG
90
Which enzyme breaks down fats?
Pancreatic lipase
91
How does TAG present itself in the GIT?
As large lipid droplets that are insoluble in water
92
Is lipase a water soluble enzyme?
Yes
93
What does pancreatic lipase break TAG down into?
Monoglyceride + 2 FA
94
Why is gut motility in the small intestine important?
Breaks fat globules apart into smaller droplets
95
What is emulsification?
Dividing large lipid droplets into smaller droplets
96
Why is emulsification vital?
As it increases the surface area of the fat therefore allowing more accessibility for LIPASE action
97
What 3 things does emulsification require?
Mechanical disruption Emulsifying agent Amphiphatic molecule
98
What is an amphiphatic molecule?
A molecule that has a polar and a non-polar section
99
Are micelles absorbed?
No
100
What are micelles constantly doing?
Breaking down and reforming
101
Why do micelles constantly break down and reform at the surface of the villi?
To feed a small pool of monoglycerides and fatty acids that are in solution
102
What part of the fat does the villi absorb?
The freely dissolved monoglycerides and fatty acids
103
Why can monoglycerides and FA just diffuse across the cell membrane?
Because of there non-polar nature
104
Once in the cell what happens to the monoglyceride and FA?
They enter the sER | And formed back into TAG
105
Where is TAG processed in the cell/
In the Golgi apparatus
106
What are extracellular fat droplets known as?
Chylomicrons
107
Where do chylomicrons pass into?
Lacteals
108
What are lacteals the terminal endings of?
Lymphatic system
109
What are the 2 classes of Vitamins?
Fat soluble | Water soluble
110
Give examples of fat soluble vitamins
A,D,E,K
111
Give examples of water soluble vitamins
B, C folic acid
112
How are fat soluble vitamins absorbed?
They follow the same path as absorbed fats
113
How is Vitamin B12 absorbed?
Using an intrinsic factor in the stomach | By specific mechanisms in the distal ileum
114
Where is vitamin B12 stored?
In the liver
115
Why is vitamin B12 vital for the body?
Important for the maturation of RBC
116
What does vitamin B12 deficiency lead to?
Leads to the failure of RBC maturation
117
What % of daily ingested iron is absorbed into the blood?
10%
118
Where is iron stored?
Ferritin
119
When blood iron is low what does the body do?
Uses ferritin stores
120
What is hyperaemia?
When there is increased ferritin levels and therefore more iron bound to RBC
121
What is anaemia?
When there is decreased ferritin levels | As more iron has been released to the blood
122
Why do we chew?
To prolong the taste experience | Defence against respiratory failure
123
How is chewing controlled?
Somatic nerves | Skeletal muscles of the mouth and jaw
124
Describe the chewing reflex
Contraction of jaw muscles pressure of food against gums, hard plate and tongue Mechanoreceptors detect this increase in pressure Lead to a reduced pressure Contraction is stimulated again
125
What is present in saliva?
``` Water Mucins A-amylase Electrolytes Lysozyme ```
126
Is the sympathetic system inhibitory or stimulatory of saliva production?
Stimulatory
127
Is the sympathetic system inhibitory or stimulatory of saliva production?
Stimulatory
128
Describe the saliva produced when the parasympathetic nervous system takes over
Profuse watery salivary secretion
129
Describe the saliva produced when the sympathetic nervous system takes over
Small volume | Viscous saliva
130
What is the oesophagus the conduit between?
The pharynx and stomach
131
How long is the oesophagus?
25cm
132
What 4 layers does the oesophagus consist of?
Mucosa Submucosa Muscularis Externa Adventitia
133
What type of epithelium is found in the oesophagus?
Stratified squamous
134
Does the oesophagus contain smooth or skeletal muscle?
Both
135
What type of muscle is found in the upper 1/3 of the oesophagus?
Skeletal
136
What type of muscle is found in the lower 2/3 of the oesophagus?
Smooth
137
Describe the oral phase of swallowing
Bolus is pushed to the back of the mouth by the tongue
138
Describe the pharyngeal phase of swallowing
Presence of bolus Sequence of reflex contraction by pharyngeal muscles Co-ordinated swallowing centre Soft palate reflected backwards and upwards Closes of nasopharynx
139
What closes over when swallowing?
Epiglottis
140
Why doe the epiglottis close over when swallowing?
To prevent the entry of the bolus into the trachea
141
What contracts when food has entered the oesophagus?
Upper Oesophageal Sphincter
142
By what movement does food travel down the oesophagus?
Peristalsis
143
How long is food in the oesophagus for?
Approx 10 seconds
144
What happens when the bolus approaches the stomach?
The lower oesophageal sphincter relaxes
145
What are the functions of the stomach?
Temporary storage of ingested material Dissolve food particles and initiate digestion Control delivery of contents to the small intestine Sterilisation Produce intrinsic factor for Vitamin B12 absorption
146
What is the name of the outer layer of the stomach?
Serosa
147
What are the 3 layers of muscularis externa in the stomach?
Longitudinal Circular Oblique
148
What folds are present in the stomach?
Rugae
149
What is the purpose of the rugae in the stomach?
To allow an increase in volume of the stomach without an increase in pressure
150
what are the 2 curvatures of the stomach?
Greater | Lesser
151
What does the lesser omentum join?
Liver | Lesser curvature of the stomach
152
Where does the greater omentum pass?
Greater curvature of the stomach To transverse colon Folding back on itself
153
What is the function of the fundus?
Primarily there for storage
154
Which acid is present in the stomach?
HCl
155
What is pepsinogen the inactive form of?
Pepsin
156
What does the intrinsic factor produced by the stomach act on?
Vitamin B12
157
Why does the antrum have a very thick muscular wall?
For the mixing and grinding down of solid food
158
What are the 3 muscle layers of the muscularis externa of the stomach?
Longitudinal Circular Oblique
159
Does the oesophagus have a mucous lining?
no
160
What does gastrin control the release of?
HCl and pepsinogen
161
What do mucous neck cells secrete?
Mucous
162
What do parietal cells do?
Release HCl and intrinsic factor for vit B12
163
What is the function of acid in the stomach>
To kill pathogens Create an acidic environment Aid digestion
164
What is the optimal pH for pepsin?
1.8-3.5
165
Describe the formation of acid by parietal cells in the stomach
CO2 from the blood enters the cells Reacts with water to form carbonic acid H+ is pumped out of the cell with K+ At the same time Cl- is pumped into the cell from the blood Cl- is then pumped into the stomach lumen Cl- and H+ in the stomach lumen react to form HCl
166
What are the 3 regulatory molecules that stimulate the release of HCl from parietal cells?
Acetylcholine Histamine Gastrin
167
What 3 mechanisms control acid secretion?
Neurocrine - vagus/acetylcholine Endocrine - gastrin Paracrine (locally)- histamine
168
Describe the cephalic phase
Stimuli such as smell, taste, sight of food are processed in the brain Activate parasympathetic neurons travelling in the vagus nerve increase acetylcholine production Stimulate G cells to produce gastrin Gastrin then stimulates ECL cells to produce histamine
169
Describe the gastric phase
``` Food is present in the stomach Stimulates vagal reflexes to release ACh Stimulates acid secretion G cells produce gastrin Gastrin and ACh stimulate the release of histamine ```
170
Describe the intestinal phase
Acid in the duodenum suggests stomach emptying reduces the effect of gastrin on parietal cells Switching off acid production in the cell
171
What is the effect of acid in the duodenum on the stomach ?
Stops stomach emptying
172
What are enterogastrones?
Hormones released from gland cells in duodenal mucosa
173
What are the 3 enterogastrones?
Secretin CCK GIP
174
What are enterogastrones released in response to?
acid, FA or peptides in the duodenum | The suggestion of stomach emptying
175
What are the 2 strategies that enterogastrones uses to neutralise the pH in the duodenum?
Inhibit gastrin secretion | Reduce gastric emptying by contracting the pyloric sphincter
176
What is pepsinogen?
The inactive form of pepsin as found in the stomach
177
Why does pepsin have to be in the form of pepsinogen?
Because the stomach is composed of protein and pepsin would just digest it
178
Does pepsin work in acidic or alkaline conditions?
Acidic
179
What happens to pepsin at neutral pH?
It is inactivated
180
What is the primary role of gastric mucous?
To have a cytoprotective role protect the mucosal surface from acid corrosion, mechanical injury and ensure pepsin has no protealytic function on the stomach lining
181
What cells produce the intrinsic factor in the stomach?
Parietal cells
182
What is the intrinsic factor produced by the stomach vital for the absorption of?
Vitamin B12
183
How much gastric quantity enters the duodenum from the stomach?
Only a small quantity of chime
184
What effect does CCK have on other organs in the GI tract?
Stimulates contraction of the gallbladder | Stimulates pancreatic enzyme secretion
185
What does secretin stimulate the release of from the pancreas?
Bicarbonate
186
What is GIP released in response to?
Glucose, FA and amino acids in the duodenum
187
What is the storage molecule for iron?
Ferritin
188
What does ferritin do?
Acts as a buffer for when blood iron levels are lower | Acts as a storage for iron
189
Why does the body of the stomach have athin muscle layer?
Because no mixing occurs here | primarily for storage
190
Why does the antrum of the stomach have much thicker muscle?
Because it does alot of mixing | and produces powerful contraction
191
What does the pyloric sphincter control?
The release of chime from the stomach to the duodenum
192
how many peristaltic waves are produced a minute?
3
193
Where are peristaltic waves generated?
In pacemaker cells
194
Will the slowest of fastest cells dictate the pace of the peristaltic wave?
Slowest
195
How is a peristaltic wave conveyed through the GI tract?
Through gap junctions in the longitudinal muscle layer
196
How is peristalsis stimulated?
By hormonal control | G cells producing gastrin
197
What is the effect of gastrin on peristalsis?
Increases contraction
198
What inhibits peristalsis?
The arrival of anything in the duodenum | Suggesting the stomach has emptied
199
What determines the strength of contraction in peristaltic waves?
Number of APs
200
What is released when there is acid present in the duodenum?
Secretin
201
What does secretin stimulate the release of?
Bicarbonate
202
How is secretin inhibited?
By acid neutralisation in the duodenum
203
Secretin inhibition i an example of what mechanism?
Negative feedback
204
What are the 3 parts of the pancreas?
Head Body Tail
205
Anatomically where does the head of the pancreas lie?
In the curvature of the duodenum
206
Where does the tail of the pancreas extend to?
The spleen
207
Where does the endocrine portion of the pancreas release contents to?
Bloodstream
208
What do islet cells produce?
Insuline and glucagon
209
What do insulin and glucagon do?
Control blood glucose levels
210
Where does the exocrine portion of the pancreas secrete to?
The cavity of the duodenum
211
What are the functional unit of acinar cells?
Lobules
212
How are lobules of the pancreas connected?
Via intercalated discs
213
What does the pancreatic duct eventually join?
The common bile duct
214
Where do the bile ducts and pancreatic duct join?
At the sphincter of oddi
215
What is the purpose of the accessory pancreatic duct?
Provides an alternative route if the main pancreatic duct is obstructed
216
What is the exocrine portion of the pancreas responsible for?
The digestive function of the pancreas | i.e the release of pancreatic digestive enzymes
217
What is the optimal pH of pancreatic enzymes?
Neutral
218
Which cells of the pancreas release enzymes?
Acinar cells
219
Which cells of the pancreas release hormones?
Islet cells
220
What do acinar cells store enzymes in the form of?
Inactive zymogen granules
221
Why do acinar cells store enzyme as zymogen?
to prevent autodigestion of the pancreas
222
Where is enterokinase found?
bound to the brush border of duodenual enterocytes
223
What do enterokinases do?
Convert trypsinogen to trypsin
224
What does trypsin do?
Converts all other zymogens to active forms
225
What do proteases do?
Cleave peptide bonds
226
What do nucleases do?
Hydrolyse DNA/RNA
227
What do elastases do?
Stimulate collagen digestion
228
What do phospholipases do?
Convert phospholipids to amino acids
229
What do lipases do?
Convert TAG to FA and glycerol
230
What does alpha-amylase do?
Converts starch to glucose+maltose
231
What is Zymogen secretion stimulated by?
CCK
232
What is the largest single organ in the body?
Liver
233
Where is the liver located?
In the upper right quadrant of the abdomen
234
What are the 2 major lobes of the liver?
Right and left
235
What are the 2 minor lobes of the liver?
Caudate | Quadrate
236
Where do the pancreatic and common bile duct drain into?
Sphincter of Oddi
237
What is the bare area of the liver?
Small diaphragmatic surface not surrounded by peritoneal cavity
238
What shape are lobules?
Hexagonal
239
What is present at the corners of lobule?
Portal triads
240
What composes the portal triad?
Hepatic portal vein Hepatic artery Hepatic duct
241
What is present in the center of lobules?
Central vein
242
Where do central veins drain into?
Hepatic veins - IVC
243
Where do hepatic cords radiate from?
From the central veins
244
What is the space between hepatic cords known as?
Hepatic sinusoids
245
Why does the liver have dual blood supply?
To have nutrient and oxygen rich blood
246
Describe the venous blood supply to the liver
O2 depleted Nutrient rich Through hepatic portal vein Go to central vein
247
Describe the arterial blood from the left side of the heart to the liver
``` O2 rich nutrient deplete travels through hepatic artery going to central veins Drained by hepatic veins ```
248
What is the alimentary role of the liver?
Production and secretion of bile
249
What is bile produced by?
The breakdown of haemoglobin in the spleen | Haem travels to the liver
250
What colour is bilirubin?
Yellow
251
What colour is bilirubin that has been modified by bacterial enzymes?
Brown
252
What colour is bilirubin that has been reabsorbed and excreted in urine?
Yellow
253
What are bile acids synthesised from?
in the iver from cholesterol
254
Where does the gallbladder drain into?
Cystic duct
255
Where does the cystic duct drain into?
The bile duct
256
What controls the release of bile and pancreatic juice into the duodenum?
Sphincter of oddi
257
To what times does the gallbladder concentrate bile?
5-20
258
What effect does CCK have on the sphincter of oddi?
Causes it to relax - i.e to open
259
What effect does CCK have on the gallbladder?
Contracts it
260
How long is the small intestine?
6 metres
261
What is the function of the duodenum?
Gastric acid neutralisation Digestion Iron absorption
262
Where is the main site of nutrient absorption?
Jejunum
263
What are the folds in the lumen of the small intestine that increase surface area?
Plicae
264
What are the finger like projections found in the small intestine?
Villi
265
What is the villi lined with?
Microvilli
266
What is the function of crypt cells?
To secrete Cl and Water
267
What effect does CF have on crypt cells?
Complete inability to transport Cl meaning water cannot be released
268
How is H2O secreted in the lumen of the small intestine?
Chloride is actively secreted into the intestinal lumen Creating an osmotic concentration gradient Dragging water with it
269
How much water does the small intestine secrete?
1500ml
270
Why is water so important in the intestinal lumen?
Maintains lumenal contents in liquid state promotes mixing Aids nutrient presentation to the absorbing surface Dilutes and washes away potentially injurious substances
271
What are the 2 types of motility in the small intestine?
Segmentation | Peristalsis
272
Describe segmentation motility
Squeezing from the middle Then the sides To allow the thorough mixing of chyme
273
Describe peristalsis motility in the small intestine
Contraction behind | Relaxation in front
274
How does segmentation produce slow migration of chyme towards the large intestine?
More chyme is pushed down than up
275
In what direction does peristalsis move?
Oral to anal direction
276
What is the start of the large intestine called?
The caecum
277
What are the 4 parts of the colon?
Ascending Transverse Descending Sigmoid
278
What type of epithelium is found in the large intestine?
Simple columnar epithelium
279
Why is the epithelium in the colon flat?
To allow chyme to pass through the colon easily
280
Describe crypt cells in the colon
Large straight crypt cells
281
What is the function of crypt cells in the colon
To produce mucous for lubrication for the movement of faeces
282
Describe the muscularis externa in the rectum
Thick compared to other regions of the GI tract
283
What are the 2 sphincters in the anal canal?
Internal anal sphincter | Voluntary external anal sphincter
284
What epithelium is in the anal canal?
Stratified squamous epithelium
285
What is broken down by bacterial in the colon?
Cellulose
286
How does the colon absorb water?
Sodium is actively transported from the lumen into the blood This creates an osmotic concentration gradient Dragging water out of the lumen Dehydrating the faeces
287
What does bacterial fermentation of undigested carbohydrate produce?
Short chain FA
288
Does the colon have an absorption role?
No - not in humans
289
Describe defacation
There is a wave on intense contraction from the colon to the rectum There is a feeling of stretch in the rectum Mechanoreceptors Defacation reflex - urge to poo
290
During constipation can the colon absorb toxins from faecal material?
No
291
What is diarrhoea?
Too frequent passage of faeces which are too liquid
292
What is the primary function of the colon?
Dehydration of chyme
293
What is the submucosa composed of?
Connective tissue
294
What is the difference between the serosa and the adventitia?
Serosa- within the peritoneal cavity | Adventitia - outwith the peritoneal cavity
295
Why does the epithelium of the gut tube differ along the GI tract?
Adaptation for function
296
From which nerve does the vagus originate?
Cranial nerve 10
297
Does a vagotomy have any effect on salivation?
No as salivation is controlled by facial nerves and glossopharyngeal nerve
298
What does the Celiac trunk branch into?
Left gastric artery Splenic artery Common hepatic artery
299
Are micelles absorbed?
No they are constantly breaking down and reforming close to the surface
300
Where are FA and monoglyceride ocmposed back into TAG when back in the cell?
Endoplasmic reticulum
301
What are the largest salivary glands?
Parotid glands
302
Why does the nasopharynx close when swallowing?
To prevent food coming up the nasal cavity
303
What type of muscle is located in the oesophagus?
Upper 1/3 - skeletal Middle 1/3 - mix of skeletal and smooth Lower 1/3 - smooth muscle
304
Glucose + galactose =
Lactose
305
Glucose + glucose =
maltose
306
Fructose + glucose =
Sucrose
307
Covering of small intestine epithelium
Simple columnar epithelium
308
Bonds that link proteins
peptide bonds
309
which enzyme carries out fat digestion?
Pancreatic lipase
310
Action of secretin
Stimulate bicarb release from pancreas | Inhibits gastric emptying
311
Action of CCK
Stimulates contraction of gallbladder And pancreatic enzyme secretion Inhibits gastric emptying
312
6 components of bile
``` bile acids lecithin cholesterol bie pigments toxic metals bicarb ```

Alimentary System (29 decks)

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