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PHGY 210 > Digestion > Flashcards

Digestion Flashcards

1
Q

What are the four accessory digestive organs?

A

Mouth
Pancreas
Liver
Gallbladder

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2
Q

What are the 6 activities of the GIT?

A 
Ingestion
Secretion
Motility
Digestion
Absorption
Defecation
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3
Q

What are the types of foods that the GIT digests best to worst?

A

Carbs (99%)
Fat (95%)
Protein (92%)

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4
Q

Which mechanisms control Propulsive, Secretory and Absorptive activities?

A

Neural and Hormonal

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5
Q

Why is the GIT longer in cadavers?

A

GIT is always under tone

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6
Q

List the layers of the GI wall

A 
From exterior to lumen:
Serosa
Muscularis externa
- longitudinal fibers
- circular fibers
Submucosa
Mucosa
- muscularis mucosae
- lamina propria
- Epithelial layer
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7
Q

What parts of the GIT are striated muscle? What tissue makes up the rest?

A

Upper third of esophagus and anus

Smooth muscle

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8
Q

True/False? The serosa is continuous with the mesentery

A

True

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9
Q

What is the role of the submucosa?

A

Loose connective tissue containing lymphatics and blood vessels

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10
Q

Where is the Enteric Nervous System located?

A

In the wall of the GIT

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11
Q

What are the three types of neurons found in the plexuses of the GIT?

A

Sensory neurons
Motor/effector neurons
Interneurons

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12
Q

True/False? The myenteric and submucosal plexuses behave independently because they are anatomically distinct

A

False

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13
Q

What are the effects of Acetylcholine on smooth muscle?

A

Excitatory

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14
Q

What are the effects of Non-Adrenergic/Non-Cholinergic NTs on smooth muscle cells?

A

Inhibitory

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15
Q

List the entities involved in short intramural reflexes

A

Stimulus -> sensory neurons -> nerve plexus -> smooth muscle/gland cell -> response

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16
Q

Parasympathetic Nerves are _____ whereas sympathetic nerves are ______
(in relation to ganglia)

A

Preganglionic

Postganglionic

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17
Q

True/False? Parasympathetic nerves act directly on smooth muscle since they don’t have a ganglion

A

False, modulate ENS

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18
Q

True/False? The PNS can act only on excitatory enteric neurons and vice versa for the SNS

A

False, PNS can inhibit inhibitory Nerves (& vice versa)

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19
Q

Sensory neurons allow for _____

A

Long Reflexes

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20
Q

Ghrelin is released by what, when? What does it do?

A

Stomach during fasting, stimulates hunger in the hypothalamic feeding centre

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21
Q

Leptin is released by what, when? What does it do?

A

Fat cells when overeating, stimulates satiety in the hypothalamic feeding centre

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22
Q

What is the Diffuse Endocrine System?

A

Largest, most diversified endocrine system in the body

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23
Q

What are the 5 most important GI hormones in the DES?

A 
Gastrin
CCK
Secretin
GIP
VIP
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24
Q

GIT regulatory hormones are released from ___

A

mucosa

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25
True/False? There is usually little/no resistance in GIT
True
26
What are the three phases of deglutition?
Oral ("voluntary") Pharyngeal Esophageal
27
What is the difference between the cortical and medullary deglutition centres?
Cortical is voluntary
28
What is more important in the pharyngeal phase, contraction of the glottis, or movement of the epiglottis?
Glottis
29
What happens in the pharyngeal phase?
Reflexes move bolus downwards, which presses on the epiglottis and in turn covers the glottis
30
What are the 4 key points of the pharyngeal phase?
1. Passages to nose, mouth, trachea are blocked 2. Apnea 3. UES relaxes 4. Pharynx muscles contract
31
True/False? The UES is closed in the absence of food
True
32
Closure of UES originates from the ____ division of the Vagus nerve
Somatic
33
During deglutition there is a _____ of impulses from the Somatic Vagus nerve resulting in muscle contraction
Cessation
34
Where does the body of the esophagus lie? What is the consequence of this?
``` Thoracic cavity Negative pressure (-5--10mmHg) ```
35
True/False? Gravity plays a major role in esophageal forces
False
36
When is a primary peristaltic wave generated?
Every time we swallow
37
What is the difference between Somatic contraction vs autonomic contraction of deglutition?
Somatic: sequential activation, from proximal to distal Autonomic: Synchronous activation, but latency becomes present distally
38
True/False? A transthoracic cut will cease propagation of the peristaltic wave
False
39
What happens if the bolus gets stuck in the esophagus?
Secondary peristalsis (initiated by local distension) (mediated by enteric and long reflexes)
40
Does the LES have a significant size increase?
No
41
True/False? The LES is contracted at rest
True
42
What is the pressure of the LES at rest?
20 mm Hg
43
Increases in the intraabdominal pressure ____ pressure on the stomach and intra abdominal LES
Increase
44
What happens during hiatus hernia?
The LES is displaced into the thorax - Intra abdominal pressure increases do not increase LES pressure
45
True/False? GIT Hormones modulate the LES
False (not at physiological doses)
46
What lowers resistance in LES?
Progesterone
47
What are the three components of the stomach?
Fundus Body Antrum
48
Which section of the stomach is thickest?
Distal
49
How is the stomach wall different from the rest of the GIT?
Gastric mucosa - Consists of folds ("rugae") Contains many different cells arranged in pits and glands Muscularis externa (contains extra layer of smooth muscle)
50
What is the volume of an empty stomach?
50 mL
51
How does the stomach accomodate a meal?
Receptive relaxation (in proximal stomach ONLY)
52
True/False? Receptive Relaxation is one of the deglutition reflexes
True
53
Which section of the stomach performs peristalsis?
Antrum
54
What is the purpose of the antrum?
Physical disruption and regulated propulsion
55
What determines the amplitude of peristaltic waves?
Magnitude of stimulus
56
What determines the frequency/Direction/Velocity of Peristalsis?
Electric characteristics of smooth muscle
57
True/False? The upper stomach has a steady resting potential
True
58
What would you observe if you measure the electrophysiology of the distal stomach?
You would see rhythmic waves of partial depolarization
59
How often does the distal stomach undergo partial depolarization? What are these waves called?
Every 20 seconds, Basic Electrical Rhythm | or Electrical Control Activity
60
True/False? BER/ECA occur with delay more distally in the stomach
True
61
What is Electrical Response Activity?
The Spikes along the peak of BER Depolarization, associated with contraction
62
Where does the BER originate from?
The interstitial Cells of Cajal (maybe)
63
ERA spikes are dependent on what ion?
Ca
64
How to spikes propagate?
Gap junctions
65
Strength of ERA becomes ____ and ___ as it approaches the Pyloric sphincter
Stronger | Wider
66
What happens when the BER reaches the pyloric sphincter?
Antral systole: The sphincter closes
67
True/False? The pyloric sphincter is closed at rest
False
68
What is the main mechanism for gastric emptying of liquids?
Emptying due to dP between proximal stomach and duodenum Normally dP is smol due to Receptive relaxation - Vagotomy to proximal stomach - dP is large - Vagotomy to distal stomach: not much change
69
How does gastric emptying of solids work
Stored in fundic resevoir | Distal stomach acts as antral pump
70
True/False? Factors in the duodenum also control the rate of gastric emptying/antral peristalsis
True
71
What are the factors in the duodenum that also control the rate of gastric emptying/andtral peristalsis?
``` Distension pH < 3 Osmolarity Chemical composition Fat >> Protein >> Carbohydrates ```
72
What factors increase stomach motility?
Gastric factors
73
What factors will decrease stomach motility?
Duodenal factors
74
Which parts of the GIT are involved with vomiting?
None Vomiting results from the action of the diaphragm and abdominal muscles to increase intraabdominal pressure (GIT is passive)
75
What causes the unpleasant symptoms often associated with vomiting?
Imbalance between parasympathetic and sympathetic activities (i.e. sweating, vasoconstriction, salivation, alternating bradycardia/tachycardia) All precede/accompany vomiting
76
What causes vomiting?
Afferent impulses to Vomiting Center (can arise from many places) Agents in blood act on Chemoreceptor Trigger Zone in medulla (distinct from vomiting center, outside BBB) CTZ sends signals to vomiting center Vomitinc center is Necessary for vomiting
77
What are the three stages of vomiting?
Nausea (psychic experience) Retching (abrupt, uncoordinated respiratory movements with glottis closed) Emesis (actual expulsion of upper GIT contents)
78
What are the processes of emesis?
Individual takes deep breath, glottis closes, abdominal muscles contract, exerting pressure on gastric contents Emesis is completed with the reversal of thoracic pressures (negative to positive) as the diaphragm is displaced upwards, forcing esophageal contents to be expelled through mouth
79
Where does most digestion/absorption of nutrients take place?
Small intestine
80
What are the three regions of the small intestine?
Duodenum Jejunum Ileum
81
What are the 4 functions of the USI (upper small intestine)
Neutralization (chyme entering from the stomach is neutralized, not protected like stomach) Osmotic Equilibration (chyme will be isotonic by the time it leaves duodenum) Digestion Absorption
82
What consitutes the intestinal juice secreted by the small intestine?
Water, mucus and Ions
83
Which juices are secreted into the small intestine?
``` Intestinal juice Pancreatic Juice (enzymes) ```
84
Where are brush border enzymes located?
Attached to the villi of small intestine cells
85
Define mechanical and chemical digestion
Mechanical: involves segmentation Chemical: Occurs as chyme mixes with pancreatic juice, intestinal juice, and bile
86
How are intestinal contractions governed?
By electerical characteristics of smooth muscle (BER/ECA) ERA - number determines amplitude of contraction
87
The intrinsic frequency of BER ______ systematically from proximal to distal intestine
Decreases
88
Compare the proximal vs distal small intestine in terms of 1. Frequency of BER, 2. Excitability of smooth muscle, 3. Thickness of smooth muscle, 4. Frequency and amplitude of contractions
1. Greater in small 2. Greater in small 3. Greater in small 4 Greater in small
89
What is the most common type of contractile activity after a meal? What is its function?
Standing rings of contraction - Segmentation Myogenic response to distension ENS organizes contraction over a length of SI ANS and hormones modulate Functions to mix contents and slowly propulse towards distal intestine
90
Why are contents of the small intestine propulsed aborally?
Because the contractions are more vicorous and frequent proximally
91
What method of prepulsion is predominant in the small intestine, Peristalsis or Segmentation?
Segmentation | In the Intestine, peristalsis is Infrequent, irregular, weak, shallow, and only travels for short distances
92
How is intestinal peristalsis mediated?
A series of local reflexes Involves interaction of longitudinal/circular muscle Modulated by ANS and HORMONSE
93
Can the frequency of intestinal peristalsis exceed the frequency of BER?
NO
94
Can intestinal peristalsis continue without an autonomic nervous system?
NO
95
Describe the law of the intestine
Radial stretch activates receptors Neural mediation causes 1. Contraction of longitudinal muscle and relaxation of circular muscle AHEAD of bolus 2. Relaxation of longitudinal muscle and contraction of circular muscle BEHIND bolus
96
Is the ileocecal sphincter typically open or closed?
Closed
97
Is the Colon Contractile Activity similar to SI?
Yes, but Slower, Sluggish, Irregular
98
What are the functions of the colon?
Mixing (promotes absorption of water/ions) Propulsion (slow - ~60h for conversion of chyme to feces) Storage
99
How is motor activity governed in the colon?
Segmentation and peristalsis (governed by IRREGULAR BER)
100
What happens to the activity in the colon/SI after intake of a new meal?
activity is increased
101
What are the long reflexes of the GIT that are stimulated by a new meal? What do they do?
Gastroileal Reflex Gastrocolic Relex Ileocolic Reflex Empty stomach contents into intestine to make room
102
What happens to GI motility during the interdigestive period?
Organized into intense pattern of cyclic myoelectric activity - Recurring at regular (~90 min) intervals - Moving sequentially over DISTAL STOMACH AND SMALL INTESTINE "Migrating myoelectric complex" or MMC
103
Describe the three phases of the MMC
``` Phase I (60 min) - no spike potentials/contractions Phase II (20 min) - Irregular Spike potentials and contractions Phase III (10 min) - regular spike potentials and contractions ```
104
True/False? The MMC is in phase throughout the GIT
False | It is offset to maintain a constant propagation rate
105
What is the function of the MMC?
"Housekeeping" to sweep out all the trash in your system (because the pyloric sphincter is open at rest, large undigestibles can leave)
106
What are the three types of enzymes involved with digestion?
Amylases Proteases Lipases
107
Regulation of digestion is predominantly _____ in the upper GIT and becomes preogressively _____ near the large intestine/colon, with the midpoint being ______
Nervous (ANS) Hormonal (Gut Peptides) Small intestine
108
What are the three mouth glands that produce saliva?
Parotid Submandibular Sublingual
109
What do amylases do?
Breakdown of polysaccharides to disaccharides
110
What enzyme does the tongue produce?
Lingual lipase
111
Saliva is unique in that it is the only ________ solution in the body
Hypotonic
112
What ions are present in saliva?
Na K Cl and HCO3
113
What is the pH of saliva?
6.5-7
114
What are the important proteins in saliva?
Ptyalin and mucin
115
How is salivary gland secretion unique in terms of regulation
It is the only case where PNS and SNS do the same thing | Parasympathetic releases more though (ACh)
116
What triggers salivation?
perception through "higher Centers" in cortex feeding into "salivary centers" in medulla or Sensory receptors in mouth acting on salivary centers Salivary centers parasympathetically affect salivary glands
117
What are the 3 phases of secretion ?
Psychic (conditioned reflex) Gustatory (taste) These two make up the cephalic phase (Gastric/Intestinal)
118
What is the most important ion in gastric juice?
H+
119
What is the pH of gastric juice?
1-2
120
What are the proteins in gastric juice?
Pepsinogen (zymogen, becomes pepsin) Intrinsic Factor (for vitamin B absorption) Mucin
121
Where are acid, enzymes and IF released in the stomach?
In the fundus and body (not antrum)
122
Describe the various gastric glands of the fundus and corpus, and the enzymes they secrete
Parietal cell - HCl Chief cell - Pepsinogen Mucus neck cell - Mucin
123
What is the purpose of canaliculi?
To increase surface area
124
Describe the pathway for HCl secretion in parietal cells
1. Cl- entering the cell is actively transported across the canalicular membrane 2. H+ (available from the dissociation of intracellular water) is actively pumped into the canaliculi in exchange for K+ 3. The secretion of H+ leaves an escess of OH- in the cell, resulting in an increase in intracellular pH 4. The change in pH causes CO2 to diffuse into the cell from plasma, which combines with water to form H2CO3 (Using carbonic anhydrase) 5. H2CO3 reacts with the excess OH- to yield H2O and HCO3- 6. HCO3- diffuses into the circulation, restoring intracellular status quo and giving rise to increased alkalinity in VENOUS blood 7. Water moves into canaliculi passively
125
What are the functions of HCl?
- Precipitates soluble proteins (allowing them to stay longer in stomach) - Denatures proteins (to be digested better) - Activates Pepsin (provides optimal pH for pepsin activity)
126
How is pepsinogen activated into pepsin?
Low pH from HCl AND Through autocatalysis
127
What is the only secretion in the stomach essential to life?
Intrinsic Factor
128
What is intrinsic Factor?
A glycoprotein secreted by parietal cells that is required for the absorption of Vitamin B12 in the ileum
129
What happens if you don't have Intrinsic Factor?
Pernicious anemia
130
Where is Mucin secreted in the stomach?
All surface epithelial cells Cardiac/pyloric tubular glands Mucous neck cells (in fundus and corpus)
131
What is the Mucibicarb layer?
A layer of mucous gel and CO2 that protects surface epithelial cells from the harsh pH of stomach acid
132
What is the layer Between the Mucous Gel and Surface Epithelial cells?
The Gastric Mucosal Barrier (apical surfaces and tight junctions)
133
What are the stomach's 3 methods of protection from the gastric mucosa?
Muci-bicarb layer GMB Rapid Cell turnover or "re-epithelialazation"
134
What are the two factors contributing to ulcers?
Weak barrier (Aspirin and NSAIDs) or Excessive HCl output (Gastrin-producing tumors)
135
What are the two types of enteric neuron that regulate secretion?
Cholinergic (+) and NANC (-)
136
What is a result of sympathetic tone on the stomach that is not a release of enzyme?
Vasodilation
137
What are secretagogues?
Amino acids/partially digested proteins which act on gastrin-releasing cells (G-cells)
138
Which cell is affected by gastrin release? How is it affected?
``` Parietal cells (HCl released) Gastrin work on heart which then acts on parietal cells (somehow) ```
139
Gastrin is released by endocrine cells in the antrum in response to which cells?
Secretagogues (products of protein digestion) Local enteric reflexes (distention in antrum) Vagally-mediated reflexes (eg vago-vagal reflexes)
140
True/False? Gastrin release is self-regulating
True
141
What are the physiological roles of gastrin?
``` Stimulates HCl Secretion Trophic effect (stimulates production of more parietal cells) ```
142
What role does Histamine play in digestion?
Lots of histamine in gastric mucosa, Histamine administration elicits large volumes of gastric juice with lots of HCl
143
What is the Common mediator hypothesis? Is it correct?
Gastrin and ACh cause Histamine release which represents the FINAL local COMMON CHEMOSTIMULATOR NO
144
What is the Separate receptor Receptor Interaction hypothesis?
There is an interaction among 3 separate receptors (Histamine, ACh, Gastrin) Blockade/Stimulation of one receptor, changes the properties of one/both of the other 2 receptors
145
What is the Permissive Hypothesis?
Histamine is constantly released and presented to the parietal cells as a tonic background, sensitizing them to other stimuli Blocking this tonic/background release of Histamin (or using H2-receptor antagonists) inhibits acid secretion (in response to ACh and Gastrin
146
How does the heart act on the Parietal cell to release HCl
We don't know (Gastrin? Entero-Oxyntin?)
147
True/False? Both Motor and Secretory activities of the stomach (at any given moment in time) reflect a balance between Excitatory and Inhibitory influences on the Muscular and Glandular cells in the gastric wall
True
148
What are the 3 pre intestinal changes?
- Meal is reduced to semi-liquid consistency - Acidified, osmotic pressure - Limited Digestion Some polysaccharides -> Disaccharides Some proteins -> polypeptides Lipids -> Di/monoglycerides, fatty acids
149
What happens in the upper intestine?
Chyme Neutralization Osmotic equilibration Digestion continues ABsorption begins
150
What is the exocrine portion of the pancreas made up of?
Acini, made of Duct cells and acinar cells | Acinar cells secrete enzymes, Duct cells secrete bicarbonate-rich fluid
151
Where is pancreatic juice released? How does it travel?
Duodenum | Pancreatic duct
152
What enzymes are found in pancreatic juice?
``` Pancreatic amylase Trypsin Chymotrypsin Elastase Pancreatic Lipase Ribonuclease Deoxyribonuclease ```
153
Describe the duct between the liver, pancreas and duodenum and their relation to each other
Bile flows from liver in common hepatic duct Bile flows from Gallbladder in Cystic duct Common hepatic duct meets up with Cystic duct to form common bile duct Pancreatic fluid flows down pancreatic duct Meets up in Ampulla of Vater and is released into duodenum (under control of sphincter of Oddi)
154
What is the key electrolyte in pancreatic juice?
HCO3- (juice is more basic)
155
How is trypsin formed and what does it do?
IN SMALL INTESTINE Trypsinogen becomes Trypsin using enterokinase Activates all proenzymes (trypsin inhibitor inactivates trypsin)
156
How are fats broken down in the small intestine?
Pro-colipase is activated by trypsin Triglycerides are broken down by lipase (and colipase) into FA, di-mono glycerides Bile salts
157
What does the liver secrete?
Bile
158
How does the liver aid in carbohydrate metabolism?
After a meal when blood glucose is high, the liver converts glucose to glycogen/triglycerides (storage)
159
How does th eliver aid in lipid metabolism?
``` Stores some triglycerides Breaks down fatty acids to generate ATP Synthesizes lipoproteins Synthesizes cholesterol Uses cholesterol to make bile salts ```
160
How does the liver aid in protein metabolism?
Deaminates amino acids so that the amino acids can be used for ATP production
161
What are the main non-digestion functions of the liver?
``` Processing of drugs and hormones Excretion of bilirubin Synthesis of Bile Salts Storage (glycogen, Vitamins, Minerals) Phagocytosis (kupffer cells) Activation of Vitamin D ```
162
What do bile salts do?
Emulsify fats to make them more easily digested
163
True/False? Bile is secreted from the liver only after meals, with more bile being secreted after a fat-rich meal
False, bile is secreted continuously
164
What are the 3 functions of the gallbladder?
Concentrates solids Reduces pH Increases viscocity
165
True/False? The gallbladder does not synthesize its own bile salts
True
166
When is a cholecystectomy a problem?
If you eat a lot of fat (Otherwise fine)
167
How are most bile salts reabsorbed into portal blood?
Enterohepatic Circulation
168
What is the difference between the hepatic vein and the hepatic portal vein?
Hepatic: Liver-heart | Hepatic portal: SI-Liver
169
What happens if more Bile Salt is returned via portal blood?
Larger VOLUME of bile secreted (+ve feedback)
170
What happens to bile volume if we remove the ileum?
Decreases (less +ve feedback)
171
The more bile salt returned in portal blood, the ___ the amount of NEW bile salts being synthesized
Smaller (negative feedback)
172
What will happen to bile salt synthesis if we remove the ileum?
Increase (less -ve feedback)
173
What happens without bile salts?
Cholesterol precipitates and gives rise to gallstones
174
Absorbtion of what two species are inhibited by Bile Salts?
Na+ and H2O
175
What happens if there is excess bile salt in colon?
Diarrhea
176
What do choleretics do?
Cause the LIVER to secrete a larger volume of bile
177
What do Cholagogues do?
Increase the emptying of the GALL BLADDER
178
What happens to bile/pancreatic juice regulation under vagal tone?
Liver: + GB Contraction/sphincter relax: +++ Pancrease (low vol/high enzyme/low pH): +++ Pancreas (High vol/low enzyme/high pH): -- Cephalic phase, prepares rest of GIT for meal
179
What does gastrin do to bile/pancreatic juice regulation?
Liver: + GB Contraction/sphincter relax: + Pancrease (low vol/high enzyme/low pH): + Pancreas (High vol/low enzyme/high pH): + Gastric phase, not much effect
180
What does CCK do to bile/pancreatic juice regulation?
Liver: -- GB Contraction/sphincter relax: +++ Pancrease (low vol/high enzyme/low pH): +++ Pancreas (High vol/low enzyme/high pH): -- Released during high fat/protein meal
181
What does Secretin do to bile/pancreatic juice regulation?
Liver: + (vol/HCO3) GB Contraction/sphincter relax: -- Pancrease (low vol/high enzyme/low pH): -- Pancreas (High vol/low enzyme/high pH): +++ Released during low pH in duodenum
182
What do bile salts do to bile/pancreatic juice regulation?
Liver: +++ GB Contraction/sphincter relax: -- Pancrease (low vol/high enzyme/low pH): -- Pancreas (High vol/low enzyme/high pH): -- Feedback looping
183
Where are crypt cells found?
In the crypt region of small intestine villi
184
Do crypt cells secrete any enzyme?
No, but they secrete a large amound of alkaline fluid called "Succus Entericus" (Villi don't secrete anything)
185
How do Villi complete digestion?
Enterocytes in Villi synthesize digestive enzymes which remain in brush border, and absorb nutrients/fluids
186
True/False? Crypt cells mature as they migrate up out of the crypt region into the villus region, whereas the cells at the tip build into dense peaks
False, but cells at tip apoptose and slough off into lumen
187
Name the 6 reactions that take place in the microvillus of the brush border (substrate, product, and enzyme)
Trypsinogen (enterokinase) trypsin alpha dextrin (alpha destrinase) n x glucose Sucrose (sucrase) glucose, fructose Lactose (lactase) glucose, galactose Maltose (maltase) 2 x glucose peptide (aminopeptidase) Amino acid Nucleotide (nucleosidase) base, pentose, phosphate
188
How are monosaccharides absorbed?
Through facilitated diffusion into blood capillary of villus
189
How are amino acids absorbed?
Through facilitated diffusion into blood capilary of villus
190
How are short chain fatty acids absorbed?
Through simple diffusion into blood capilary of villus
191
How are tryglycerides absorbed?
Through simple diffusion of a chylomicron into lacteal of villus, then into left sublavian vein (near heart)
192
True/False? the large intestine takes up the last amount of nutrients left behind in SI
False
193
What is secreted by the colon?
Alkaline, mucous, (no digestive enzymes/absorption) | BACTERIAL ACTIVITY
194
How much digestive fluid is secreted in a day? How much is absorbed?
7L of secretions, ~9L absorbed
195
True/False? Most of absorption is REabsorption
True
196
What is the only GI organ essential to life?
SI
197
What does the Duodenum absorb the most?
Iron, Calcium, CHO, Proteins, Lipids, Sodium, Water
198
What does the Jejunum absorb most?
CHO Proteins, Lipids, Sodium Water
199
What does the Ileum absorb most?
CHO, Proteins, Lipids, Sodium, Water, Vitamin B12, Bile Acids
200
What are the requirements for absorption?
Adequate Digestion Adequate sites of absorption Adequate transit time for absorption Adequate cofactors/transporters
201
True/False? Oligopeptides may be absorbed faster than free amino acids
True

PHGY 210 (5 decks)

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