The Digestive System 2 Flashcards
(115 cards)
1
Q
How many chambers are in the ruminant stomach?
A
4
2
Q
the first 3 chambers in the ruminant stomach that are nonglandular
A
Forestomaches (Proventriculus)
3
Q
List the 3 chambers within the proventriculus
A
- Reticulum
- Rumen
- Omasum
4
Q
does not produce digestive enzymes
A
Nonglandular
5
Q
the large expansible chamber of the ruminant stomach where fermentation occurs
A
Rumen
6
Q
the 4th chamber in the ruminant stomach that is glandular
A
Abomasum
7
Q
Give the 2 components of the reticulorumen
A
- Reticulum
- Rumen
8
Q
the “true stomach”
A
Abomasum
9
Q
the “book stomach”
A
Omasum
10
Q
the “paunch”
A
Rumen
11
Q
the “honeycomb”
A
Reticulum
12
Q
muscular folds that divide the rumen into the dorsal sac, ventral sac, and two caudal sacs
A
Pillars
13
Q
the link between the esophagus and the omasum that plays a critical role in young ruminants by preventing milk from spilling into the reticulorumen and fermenting
A
Esophageal (Reticular) Groove
14
Q
List the 3 types of contractions in the reticulorumen
A
- Primary Contractions
- Rumination
- Eructation
15
Q
the contractions of the reticulorumen that help ensure adequate movement of the contents back and forth between the reticulum and the rumen, serve to separate particles based on size, and provide the force necessary to move the liquid contents from the reticulorumen into the omasum
A
Primary Contractions
16
Q
the contractions of the reticulorumen in which the ingesta moves up from the reticulorumen into the oral cavity where additional saliva and continued chewing help to break down the coarse plant materials further
A
Rumination
17
Q
the contractions of the reticulorumen responsible for the release of gases such as carbon dioxide and methane produced during fermentation
A
Eructation
18
Q
the condition in which carbon dioxide and methane accumulate without being released, the reticulorumen expands too much, and results in compressed thoracic and abdominal organs, compromised blood flow to abdominal organs, lung function interference, tissue hypoxia and even death if untreated
A
Bloat
19
Q
What are the 4 phases of rumination in the ruminant stomach?
A
- Regurgitation
- Re-salivation
- Re-mastication
- Re-swallowing
20
Q
the phase of rumination in which an antiperistaltic wave moves bolus into the oral cavity
A
Regurgitation
21
Q
the phase of rumination in which a bolus has more saliva added to it in order to help break down the plant materials further
A
Re-Salivation
22
Q
the phase of rumination in which a bolus is chewed again in order to help break down the plant materials further
A
Re-Mastication
23
Q
the final phase of rumination
A
Re-Swallowing
24
Q
bacteria in the reticulorumen that break down starch and soluble carbohydrates into volatile fatty acids (VFA)
A
Amylolytic Bacteria
25
bacteria in the reticulorumen that break down components of cell walls (cellulose, hemicelluloses, pectin) into volatile fatty acids (VFA)
Cellulolytic Bacteria
26
What is the main source of energy for ruminants?
Volatile fatty acids (VFAs)
27
enzymes released by rumen bacteria that break down proteins into smaller peptide chains that are then absorbed by the microbes, further hydrolyzed inside the cell, and culminate the production of amino acids
Peptidases
28
compounds that can be converted by microbes into ammonium which is then synthesized to make microbial amino acids
Non-Protein Nitrogen (NPN) Compounds
29
the production of glucose by the liver from noncarbohydrate sources
Gluconeogenesis
30
What process produces almost all glucose needed by ruminants?
Gluconeogenesis
31
What are the 3 divisions of the small intestine?
1. Ileum
2. Jejunum
3. Ileum
32
the production of glucose by the liver from noncarbohydrate sources
33
What are the 2 divisions of the duodenum?
1. Descending Duodenum
2. Ascending Duodenum
34
the longest portion of the small intestine where the bulk of chemical digestion and absorption occurs and has great range of motion due to its long mesentery
Jejunum
35
the portion of the small intestine that empties into the large intestine at the cecum, colon, or both depending on the species and is where Peyer's patches are most prominent
Ileum
36
the area where the small intestine empties into the large intestine in equines
Ileocecal Junction (Cecum)
37
the area where the small intestine empties into the large intestine in canines and felines
Ileocolic Junction (Colon)
38
the area where the small intestine empties into the large intestine in ruminants and pigs
Ileocecocolic Junction (cecum + colon)
39
aggregates of lymphoid tissue in the small intestine that help protect the animal from disease by controlling local populations of bacteria, functioning in antibody production, and aiding in filtration of fluids
Peyer's Patches
40
permanent structures in the small intestine formed by the folding of its mucosa lining
Plications
41
a structure on majority of the surface area of the small intestine formed from its microvilli that contain enzymes responsible for membranous digestion
Brush Border
42
fingerlike projections on the mucosa of the small intestine that move back and forth to help move liquid contents into close contact with the mucosa
Villi
43
lymphatic capillaries found in the villi of the small intestine that carry absorbed lipids and fat-soluble substances to the thoracic duct
Lacteals
44
a hormone secreted by the small intestine responsible for inhibiting gastric emptying, triggering gallbladder contraction, and the secretion stimulation for pancreatic digestive proenzymes, bicarbonate, and enteropeptidase
Cholecystokinin (CCK)
45
What 3 things stimulate cholecystokinin secretion?
Chyme entering the small intestine with a:
1. High amino acid concentration
2. High fatty acid concentration
3. Low pH
46
a hormone secreted by the small intestine that decreases HCl production in the stomach and increases pancreatic and biliary bicarbonate secretions
Secretin
47
What 2 things stimulate secretin secretion?
Chyme entering the small intestine with a:
1. High fatty acid concentration
2. Low pH
48
a substance secreted by the pancreas and liver that helps neutralize the acids leaving the stomach to ensure the pancreatic digestive enzymes are most effective
Bicarbonate
49
groups of cells containing several different cell types that each produce their own hormone and carry out the endocrine functions of the pancreas
Pancreatic Islets
50
pancreatic cells that secrete insulin to lower blood glucose levels
Beta Cells
51
pancreatic cells that secrete glucagon to raise blood glucose levels
Alpha Cells
52
pancreatic cells that secrete somatostatin to inhibit gastric secretion and somatropin release
Delta Cells
53
a cluster of epithelial cells that release their secretions into the lumen, merge with other lumina to form ducts that eventually converge into the pancreatic duct
Acini (sg Acinus)
54
Where does the pancreatic duct empty into?
Duodenum
55
pancreatic enzymes that break down nucleic acids into nucleotides
Nucleases
56
List 4 functions of the liver
1. Secretion of substances essential for nutrient digestion and absorption
2. Synthesizing nutrients + regulating release into bloodstream
3. Excreting toxic substances
4. Producing most of the plasma proteins, cholesterol and many of the blood coagulation factors
57
Give the 2 surfaces of the liver
1. Diaphragmatic Surface
2. Visceral Surface
58
the convex surface of the liver
Diaphragmatic Surface
59
the surface of the liver in contact with the right kidney, stomach, duodenum, colon, and jejunum
Visceral Surface
60
the attachment between the liver and the diaphragm
Falciform Ligament
61
microscopic divisions of the liver
Hepatic Lobules
62
What 2 blood vessels does the liver receive blood from?
1. Hepatic portal vein
2. Hepatic artery
63
the blood vessel that carries blood from the intestines to the liver
Hepatic Portal Vein
64
the blood vessel that carries blood from the heart to the liver and branches off the celiac artery
Hepatic Artery
65
abnormalities of the portal vein in which the portal vein doesn't deliver blood to the liver but instead caries blood from the intestines to the caudal vena cava
Portosystemic Shunts
66
branches of the hepatic portal vein, hepatic artery, and the bile duct bound into a portal tract that empties into the sinusoids of the liver
Hepatic Triads
67
liver cells
Hepatocytes
68
macrophages in the liver sinusoids that engulf foreign substances
Kupffer Cells
69
bile ductules located between individual hepatocytes that travel in the opposite direction from the blood and empty into large bile ductules
Canaliculi
70
Necessary for lipid digestion in the intestines
Bile
71
structures through which bile exits the liver and empties into the common bile duct
Hepatic Ducts
72
the structure that carries bile from the liver to the gallbladder or duodenum depending on the species
Common Bile Ducts
73
a small structure that connects the gallbladder to the common bile duct and allows bile to enter and leave the gallbladder
Cystic Duct
74
the structure that controls the entrance of the bile duct into the duodenum
Sphincter of Oddi
75
Concentrates + stores bile until needed
Gallbladder
76
the pathway for bile from the liver to the intestine to the hepatic portal vein and back to the liver
Enterohepatic Circulation
77
a breakdown product of hemoglobin that is eliminated through bile
Bilirubin
78
red pigment
Heme
79
green pigment
Biliverdin
80
yellow to orange pigment
Bilirubin
81
yellow to orange pigment based on degree of oxidation
Urobilin
82
brownish pigment
Stercobilin
83
Where can disruptions in bilirubin excretion occur?
Anywhere in the pathway
1. Prehepatic
2. Hepatic
3. Posthepatic
84
What happens if bilirubin excretion is interrupted at any point?
1. Blood bilirubin levels elevate
2. Animal becomes icteric
3. Develops bilirubinemia
85
a condition characterized by an abnormal increase of bilirubin in the blood
Bilirubinemia
86
the abnormal increase of bilirubin in the blood due to too many RBCs hemolyzed in circulation which causes the amount of bilirubin to overwhelm a normally functioning liver
Prehepatic Bilirubinemia
87
the abnormal increase of bilirubin in the blood due to a malfunctioning liver with hepatocyte that have a reduced ability to conjugate bilirubin
Hepatic Bilirubinemia
88
the abnormal increase of bilirubin in the blood due to obstruction of the bile duct or impairment of bile flow within the canaliculi
Posthepatic Bilirubinemia
89
a condition that prevents or slows the flow of bile through the bile ducts which causes a buildup of substances that would normally be excreted through the bile
Cholestasis
90
What are the 2 types of cholestasis?
1. Extrahepatic Cholestasis
2. Intrahepatic Cholestasis
91
the obstruction of the common bile duct that prevents or slows the flow of bile through the duct which causes a buildup of substances that would normally be excreted through the bile
Extrahepatic Cholestasis
92
the impairment of bile flow within the canaliculi which causes a buildup of substances that would normally be excreted through the bile
Intrahepatic Cholestasis
93
the conversion of glucose into energy
Glycolysis
94
the major storage form of glucose
Glycogen
95
the process in which glycogen can be broken down to glucose monomers when the animal needs to use glucose as an energy source and can occur when the animal is in the postabsorptive state and glucose is no longer readily available
Glycogenolysis
96
What 3 substances are used in gluconeogenesis?
1. Pyruvate
2. Lactate
3. Glycerol
97
a process of localized contractions of circular muscle in the small intestine used to mix chyme and increase its contact with mucosal enzymes and absorptive surfaces
Segmentation
98
pancreatic enzymes that break proteins at internal points along the polypeptide chains which result in smaller peptide chains and do not release free amino acids
Endopeptidases
99
pancreatic enzymes that break proteins at the ends of the polypeptide chains and release free amino acids
Exopeptidases
100
List the 4 steps to digest and absorb lipids
1. Emulsification
2. Hydrolysis
3. Micelle Formation
4. Absorption
101
The large intestine consists of what 4 things?
1. Cecum
2. Colon
3. Rectum
4. Anus
102
a blind diverticulum at the beginning of the large intestine that varies in size based on species and diet
Cecum
103
List the 3 divisions of the colon
1. Ascending Colon
2. Transverse Colon
3. Descending Colon
104
the terminal portion of the large intestine where stool is stored temporarily until defecation occurs
Rectum
105
the opening of the gastrointestinal tract for the elimination of stool
Anus
106
List the 4 motility patterns of the large intestine
1. Segmentation
2. Peristalsis
3. Antiperistalsis
4. Mass Movement
107
the movement in the large intestine consisting of a period of intense propulsive activity, moving the contents of the large intestine toward the rectum
Mass Movement
108
What are 2 important functions of the large intestine?
1. Water absorption
2. Ion absorption
109
the reflex stimulated by rectum sensory receptors as feces are transported and causes the colon and rectum to contract while relaxing the inner anal sphincter muscle
Defecation Reflex
110
a skeletal muscle capable of delaying defecation in some species
Outer Anal Sphincter
111
a condition where teeth form erosions which are then covered with gingival tissue
Tooth Resorption
112
gingival tissue
Calculus
113
an autoimmune disease in which antibodies target the receptors for acetylcholine, preventing the transmission of nerve impulses to the skeletal muscles, thereby preventing contraction
Myasthenia gravis
114
abnormal esophageal dilation that results in food improperly moving down the esophagus and frequent regurgitation of undigested food
Megaesophagus
115
a protective mechanism that provides animals with the ability to remove harmful or toxic substances from the stomach or upper intestine
Emesis
