Gastrointestinal system Flashcards
(140 cards)
1
Q
digestive system functions (8)
A
ingestion
propulsion
mixing
mastication
secreation
digestion
absorption
elimination
2
Q
what are the two types of digestion
A
mechanical and chemical
3
Q
how is mechanical digestion classified
A
physical disruption of food into smaller parts eg. chewing
4
Q
how is chemical digestion classified
A
using enzymes or bacteria to break down food
5
Q
what is the digestive tract
A
tubular passage way from oral cavity to anus/cloaca
6
Q
what is the digestive system
A
Digestive System = Digestive tract + Glands + Accessory structures
7
Q
what are the layers of the digestive tract
A
Mucosa
Submucosa
Tunica muscularis
Serosa/adventitia
8
Q
what is peristalsis
A
the contraction of substances through organs
9
Q
what is an Obligate Carnivore
A
must eat meat as they cannot digest plant-based food
10
Q
what is a Piscivore
A
diet that consists of mostly fish
11
Q
what is an insectivore
A
mainly consume insects, but they may also eat other small invertebrates like worms, spiders, or larvae.
12
Q
what is an Frugivore
A
primarily feeds on fruit.
13
Q
what is a Folivore
A
primarily eats leaves
14
Q
what is a Granivore
A
primarily feeds on seeds and grains
15
Q
Carnivore anatomy adaptations compared to herbivores
A
have shorter intestines
(relative to size) than
herbivores
16
Q
herbivores intestines adaptations compared to carnivores
A
very long small
intestines and
modifications for
digestion of cellulose,
such as adapted
stomachs in ruminants,
or caeca
17
Q
what are the digestive accessory organs
A
gallbladder, pancreas, liver, spleen
18
Q
role of the gallbladder
A
store and concentrate bile
19
Q
role of the pancreas
A
helps regulate blood sugars by producting insulin (from beta cells), Glucagon (from alpha cells), and produce digestive enzymes (amylase, Lipase, Proteases)
20
Q
role of the liver
A
metablism regulation, detocification, bile production, storage, bllod filtration, synthesis of cholesterol and immune functions such as pathogens in the blood stream
21
Q
role of the spleen
A
filtration of blood (removing old, damaged rb cells, filter plates), immune system function, storage of rb cells
22
Q
what is included in the fore gut
A
Oesophagus
Stomach
Liver
Gallbladder
Duodenum (Proximal)
23
Q
what is included in the midgut
A
Duodenum (Distal)
Jejunum
Ileum
Cecum
Appendix
Ascending colon
24
Q
what is included in the hindgut
A
Descending
colon
Sigmoid
colon
Rectum
25
what arterial supply is in the foregut structures
coeliac trunk
26
what arterial supply is in the midgut structures
superior/cranial mesenteric artery
27
what arterial supply is in the hindgut structures
inferior/caudal mesenteric artery
28
what is the role of the hepatic portal vein
Takes nutrients from the gut to the liver to be synthesised/detoxified
29
Venous and Lymphatic Drainage (cranial to caudal)
CISTERNA CHYLI
COELIAC LYMPH NODES
SUPERIOR MESENTERIC LYMPH NODES
INFERIOR MESENTERIC LYMPH NODES
30
Autonomic innervation in a cat (cranial to caudal)
Sympathetic chain
Vagus Nerve
Coeliacomesenteric ganglion
Caudal Mesenteric ganglion
31
what are the abdominal cavitites
SUPERIOR BOUNDARY (diaphragm, and thoracic)
INFERIOR BOUNDARY (pelvic)
32
layers of the abdominal wall (outer most to inner most)
skin, SUPERFICIAL fascia, deep fascia, transversalis fascia, parietal
33
abdominal wall layers (out to inner)
Rectus Abdominis
External Oblique
Internal Oblique
Transversus Abdominis
34
what are the arteries called that are involved in the abdominal wall supply?
Superior epigastric artery
Inferior epigastric artery
35
what is a Peritoneum
Membrane that lines the abdominal cavity (a single layer of mesothelium supported by the fibroelastic tissue)
36
what is the Retroperitoneum
the space located behind the peritoneum in the abdominal cavity
37
what are the organs in the retroperitoneum
Suprarenal glands
Aorta (and inferior vena cava)
Duodenum (2nd & 3rd parts)
Pancreas (not tail)
Ureter
Colon (ACDC)
Kidneys
Oesophagus
Rectum
38
what does the lesser omentum connect
stomach to the liver
39
what does the greater omentum cover
covers the intestines, particularly the small intestine and parts of the large intestine.
40
what is the cupids bow called
philtrum
41
what is the upper and lower lips called
superior lip and inferior lip
42
what is the oral fissure
the gap between lips
43
what is the muscle circling around the lips
Orbicularis oris
44
what is the top jaw and bottom jaw called
Maxilla and mandible
45
where are the sites of muscle attachment in the mandible
coronoid process
46
what is the palatine
a bone at the back of the hard palate
47
features of the hard palate
thick mucosa
transvers ridges (rugae)
48
features of the soft palate
innervation (sensory and motor)
Depresses to close opening into
pharynx
49
the tongue can be seperated into two parts
body (top)
root (bottom- what you cant see)
50
what is the tonge
mobile muscular organ
51
what is the tounges role
deglutiton
speech
52
what is the hyoid bone
small mobile bones that suspends the tongue and Trachea to the skull
53
what is the motor nerve that is correlated with the tongue
Hypoglossus
54
what is the sensory nerve that is correlated with the tongue
glossopharyngeal
55
layers of the teeth (outer to inner)
enamel
dentine
pulp
periodontal ligament (attaches tooth to gum)
56
what is the acrodont tooth position
straight up and shallow in the gum
57
what is the pleurodont tooth position
straight up, on the gum but mostly at the back of the gum
58
what is the thecodont tooth position
in the gum pointing straight up
59
what does diphyodonts mean
mammals who have a deciduous and a permanent set of dentition (baby and adult teeth)
60
what is polyphyodonts
tooth fish and reptiles that have multiple sets of teeth (eg. sharks)
61
from front to back- the types of teeth (4)
incisors
canines
premolars
molars
62
what is the carnivores only salivary gland
Buccal
63
the salivary gland near the ear
parotid (otid= ear)
64
the salivary gland near the tounge
sublingual
65
salivary gland near the back of the throat
mandibular
66
what do salivary gland secretions contain
salivary amylases and antimicrobial agents
67
what are the three sets of human salivary glands
parotid, sublingual, submandibular
68
what is salivation stimulated by
Parasympathetic innervation (facial and glossopharyngeal nerves)
69
what do the temporalis muscles do
closes the jaw (prominent in carnivores)
70
what do the masseter muscles do
Closes the jaw
allows lateral movement (prominent in herbivores)
71
what so the lateral pterygoid muscle do
Protrudes the mandible- important in opening of the jaw
72
what do the medial pterygoid muscle do
closes the jaw
73
what can the pharynx be divided into
nasopharynx
oropharynx
larngopharynx
74
function of the crop
Stores and soften foods before entry into proventriculus
75
chemical digestion in the stomach
pepsinogen
hydrochloric acid
rennin/chymosin
76
mechanical digestion in the stomach
churning and mixing food
increases contact between enzymes and digesta
77
why does the stomach have asymetrical growth
asymetrical growth leads to the kidney bean shape- one side grows faster
78
where does the lesser curvature attached too in the stomach
liver
79
what are the three muscle layers of the stomach
Longitudinal
Circular
Oblique
80
what is rugae
the wrinkles in the stomach- allows the stomach to stretch when food enters
81
why cant horses vomit
horses are unable to vomit- because of their osophicals and a muscular cardiac sphincter- colic
82
the order of ruminants stomach chambers
start
oesophagus
1.rument-
2.reticulum-
3.omasum-
4.abomasun-
end
83
what happens in the rument
fermentation occurs
84
what occurs in the reticulum
allows movement of fluid
85
what occurs in the omasum
responsible for squeezing fluid out
86
what occurs in the abomasum
final chamber, site of chemical digestion
87
how to identify the chambers of the stomach
rumen- papillated
reticulum- honeycomb
omsasum- small bumbs
abomasum- really wrinckly
88
what is the duodenum
first part of the small intestine, site of the foregut/midgut divide
89
what ducts enter from the duodenum
common bile duct, major duodenal papilla, main pancreatic duct
90
the process of the gallbladder and its duct system
* Ducts collect bile from R + L liver
* Fuse to drain liver
* Empty into gallbladder
* Run from gallbladder to duodenum
91
What organs is involved in the midgut
Duodenum (distal)
Jejunum
cecum
appendix
ascending colon
transverse colon
92
what is special about the midgut anatomy
no accessory glands or structures
93
what artery supplies the midgut
cranial mesenteric artery
94
what nerve controls the mid cut
parasympathetic intervention- vagus nerve
95
what are the four layers of the GI tract
1 = MUCOSA
2 = SUBMUCOSA
3 = MUSCULARIS EXTERNA
4 = Serosa
96
describe the mucosa layer of the gi tract
epithelial lining and lamina propria (Connective tissue) and smooth muscle
97
describe the submucosa layer of the gi tract
dense and irregular connective tissue
98
describe the muscularis externa layer of the gi tract
mostly 2 layers of smooth muscle
99
describe the serosa layer of the gi tract
thin layer of connective tissue
100
role of the small intestine
chemical digestion- secretion of juices (neutralise the stomach acid)
MAIN ROLE- absorption of proteins/carbohydrates/fats
101
sections of the small intestines from stomach to bowels
duodenum
jejunum
ileum
102
what is the role of the brunner's glands
secretion of alkaline mucus
103
Jejunum in human compared to animals anatomy
50/50 in humans Jejunum and duodenum
but Jejunum takes up most space in animals
104
what is supplised by the coeliac trunk
jejunum and ileum
105
Which structures drain lymph via the superior mesenteric lymph node and are innervated by the vagus nerve
mall intestine and parts of the large intestine (specifically the cecum, appendix, and the ascending colon) drain lymph through the superior mesenteric lymph node. These structures are also innervated by the vagus nerve, which plays a crucial role in parasympathetic control of digestive functions.
106
features of the jejunum
has folds (plicae circulares)
highly absorbent
Villi and microvilli increase the surface area, which increases the role of adsorption
107
features of the ileum
Less foiled structures compared to jejunum- still have villi but not increased folds
Lots of white blood cells for immunity
lymph tissue (galt)- Peyer's patches
complex network of blood vessels
Lots of fat
108
structures of the large intestine
caecum
ascending colon
transverse colon
descending colon
sigmoid colon
rectum
109
what is the ileocecal junction
part of the digestive tract where the small intestine meets the large intestine
110
What is midgut fermentation
Midgut fermentation is the digestion of cellulose by commensal bacteria in the caecum and ascending colon
111
what animals practise midgut fermentation
horses, rhinos and rabbits
112
animals that practise midgut fermentation have what stomach type
simple, sinngle chambered stomach
113
pros and cons of midgut fermentation
faster than foregut but less efficient
absorbs the soluble sugars before fermentation happens
114
pros and cons of foregut fermentation
efficient- maximises absorption for plant diets
allows large animals to eat a large meal and retreat safely to digest
115
What are caecotrophs
Caecotrophs are nutrient-rich droppings produced in the caecum and proximal colon. They contain digestible nutrients that the animal can absorb after eating them
116
What is the role of the fusus coli in digestion
The fusus coli controls muscle contractions in the colon, helping move food and waste through the intestines.
117
What are segmental and haustral contractions
These are muscle movements in the intestines that divide food into solid and liquid parts, helping to mix and push food along
118
Why do some animals eat their own soft droppings
Animals, like rabbits, eat their soft droppings (caecotrophs) to digest the nutrients a second time and absorb more of the food's nutrients
119
what is the taeniae coli
long bands of smooth muscle thay sits on the colons surface- creates pockets when colon contracts for fermentation to occur
120
what does a cows ascending colon look like
cinnamon roll.
spiralling, flat in comparison to the pig
121
what does a pigs ascending colon look like
chandelier.
spiralling downward
122
role of the colon
Absorption of salts/water
fermentation of complex carbs
excretion of faeces
produces mucas
123
Features of colon
smooth mucosa
no villi
Intestinal glands
124
midline laparotomy insertion
follows the linea adlba (MOST COMMON)
125
what surgical accesses with a paramedian incision
kidney, spleen
126
what surgical accesses with a pfannenstiel incision
pelvic/bladder/prostate
127
what surgical accesses with a rutherford-morrison incision
implantation of a kidney, colonic resection, sigmoid colostomy, caecostomy
128
early embryonic development of the gut tube layers orign
endoderm- mucosa
mesoderm- submucosa, tunica muscularis, serosa/adventita
129
What is the folding process of the early embryonic gut tube?
During the fourth week of embryonic development, the gut tube undergoes cranial, caudal, and lateral folding. This folding allows the straight gut tube to form a C-shaped structure that will later differentiate into the foregut, midgut, and hindgut
130
What are the differences between the foregut, midgut, and hindgut
Foregut: Forms the esophagus, stomach, liver, pancreas, and part of the duodenum.
Midgut: Forms the small intestine (except the duodenum), cecum, appendix, ascending colon, and two-thirds of the transverse colon.
Hindgut: Forms the distal part of the transverse colon, descending colon, sigmoid colon, rectum, and part of the anal canal.
131
How are common congenital abnormalities related to deviated developmental processes
Congenital abnormalities arise from errors in gut tube development, such as:
Esophageal atresia & tracheoesophageal fistula: Improper separation of the foregut.
Omphalocele & gastroschisis: Failure of abdominal wall closure.
Meckel's diverticulum: Incomplete obliteration of the vitelline duct.
132
what is included in the hindgut
Decending colon
stimoid colon
rectum
133
what is Teniae coli
ribbons of longitudinal muscle
contractions cause haustra to form
134
role of the rectum
Supports and stores faecal mass before defecation
135
What happens during defecation
Build-up of pressure against the walls of the rectum.
Internal sphincter relaxes to open and allow feces into the canal.
Relaxation of the external sphincter permits defecation
136
What type of muscle is the external anal sphincter
voluntary, skeletal, innervated by the pudendal nerve
137
What type of muscle is the internal anal sphincter?
Thickening of the circular muscle of the gut tube, Smooth Muscle, Innervated by Pelvic splanchnic nerves (parasympathetic), Also influenced by Sympathetic splanchnic nerves
138
what is the dentate/pectinate line
Line that divides the upper two-thirds and lower third of the anal canal
The third distal to the body is from ectoderm origin and is somatic motor and sensory innervation
The other two-thirds are derived from endoderm and are visceral motor and sensory innervation
139
what is the levator ani
symmetrical set of three deep pelvic-floor muscles
-llicoccygeus muscle
-pubococcyhues muscle
-puborectalis muscle
140
anatomy for an avian cloaca- male
from top to bottom
seminal glomus
ureter
coprodeum
urodeum
proctodeum
