Flashcards in Digestion 1 Deck (99)
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1
List the 5 functions of the digestive system
1) securing food
2) conducting and storing food
3) mechanical and chemical digestion
4) absorption of food
5) storage and disposal of waste
2
Name the 3 parts of the abdominal cavity and the sub parts
1) mouth
2) pharynx
3) alimentary canal
a. oesophagus
b. stomach
c. small intestines
d. large intestines
3
List and describe the main features of the mouth
1) maxillae and mandible - jaws
2) cheeks (buccae) and lips (labia)
3) outer vestibule - formed between lips/cheek when mouth is closed
4) mouth cavity proper - roofed by palate, laterally by teeth, and tongue on the floor
4
what does the pharynx connect and where does the oesophagus sit in relation to it
the back of the nasal and oral cavities with the oesophagus sitting dorsal to the larynx
5
Wall structure of the abdomen cavity
1) Inner lining layer (the mucosa)
- Transport nutrients and keeps out bacteria
2) Underlying connective tissue layer (the submucosa)
- Containing blood vessels and nerves
3) The major muscle layer (muscularis externa)
- Mixing and peristalsis
4) Outer connective tissue - serosa - lubricant
6
what are intrinsic and extrinsic glands give an example
intrinsic - in walls and releases secretion into lumen eg - goblet cells
extrinsic - outside the walls and delivers secretions to lumen via ducts eg - salivary glands
7
regions of the abdomen name them
2 transverse, 2 sagittal divide abdomen into 9 regions
cranial - 1. xiphoid 2. left hypochondrial region 3. right hypochondrial region
middle - 4. umbilical region 5. left lateral (fank) 6. right lateral (flank)
caudal - 7. pubic 8. left inguinal 9. right inguinal
8
what is the cranial, caudal and lateral boundry of the abdominal cavity
cranial - diaphragm
caudal - pelvic inlet
lateral - diaphragm, 3 muscles of the lateral abdominal wall - Internal and external abdominal oblique; transverse abdominal muscle and part of the pelvis (wing of the ilium)
9
what is the dorsal and ventral boundary of the abdominal cavity
dorsal - the lumbar vertebrae, the sublumbar muscles and the arms (crura) of the diaphragm
ventral - The left and right rectus abdominis muscles (strap-like; either side of midline)
10
what is the sublumbar fossa and where is it found within abdominal regions
The sublumbar fossa (can look sunken on a cow) is contained in the dorsal aspect of the flanks
11
what is peritoneum what is it composed of and its function
smooth shiny serious membrane which lines the abdominal and part of the pelvic cavity
composed of squamous epithelium which lies on connective tissue, containing blood vessels, nerves and lympatics
to secrete the watery peritoneal fluid that acts as a lubricant to decrease friction
12
what is the peritoneal cavity enclosed by, what is it divided into and how much space is contained within
peritoneum and is divided into the peritoneal portion and the pelvic portion.
little space due to great bulk of viscera
13
List the 3 main types of peritoneum and describe them
1) Parietal peritoneum- is peritoneum attached onto the wall of the abdominal cavity
2) visceral peritoneum - is peritoneum lining the external surfaces of the viscera (soft internal organs).
3) connecting peritoneum - composed of double membranes: different types
14
List the 3 types of connecting peritoneum
1) mesentery
2) omentum
3) ligament
15
What is the mesentery, examples and what it provides
peritoneum from the intestine to the dorsal wall of the abdominal cavity.
- The Common or great mesentery - connects most of the small intestine to the abdominal roof at the level of the first and second lumbar vertebrae.
- Mesocolon - attaches the colon (large intestine) to the abdominal roof and continues into the pelvic cavity as the mesorectum
- Provides access to blood vessels
16
what is the omentum and 2 examples
peritoneum that connects the stomach
- Greater omentum- passes from greater curvature of stomach to the spleen to the dorsal lumbar wall. It encloses a potential cavity- the omental bursa. - must move to get to intestines and the fat content will vary depending on animal
17
What is the ligament (abdominal cavity) and what is it not concerned with
about connecting to the liver
-reflections of peritoneum between the viscera (internal organs of the abdominal cavity), or between viscera and the abdominal wall-usually not concerned with conducting vessels and nerves.
18
where does the kidney, liver and stomach sit in the abdominal cavity
Kidney sits dorsal and not covered in peritoneum unlike everything else - most dorsal
Liver sits right up against the diaphragm
Stomach sits right under ribs usually
19
where does the dog stomach sit when empty moderately full and completely full
Empty - does not contact the abdominal wall
Moderately filled - lies against the xiphoid and left hypochondrial region
Completely full-lies primarily in contact with the xiphoid and umbilical regions ventrally, and the right and left lateral regions and can reach caudally to a transverse plane just caudal to the umbilicus. Sticking out of the rib cage
20
name the two main types of teeth and types within
brachydont teeth
Hypsodont teeth
aradicular hysodont or hypselondont - no roots
21
characteristics of brachydont and hypsodont teeth
brachydont - short crowned teeth, sole tooth type of carnivores, have a limited period of growth and eruptiononce stop stop growing
Hypsodont - high crowned teeth found in herbivores and omnivores teeth adapted to high rates of wear. prolonged growth and eruption period, root develops sometime after eruption commences
22
List the 3 main parts of a tooth
1) crown
2) neck
3) root
23
describe the crown of both types of teeth
the part of the tooth that is covered by enamel
- brachydont teeth, comprises the entire tooth above the neck
- hypsodont teeth: the ‘anatomical crown’ (body): comprises the clinical crown – the part that has erupted and the reserve crown – the part still beneath the gum line
24
describe the neck and the root of teeth
A slight constriction at the cemento-enamel junction (where the enamel and cementum meet), which is covered by free gingiva (gum) in normal healthy tooth. Present in brachydont teeth, absent in hypsodont.
-Root: Located within and anchored to the alveolus. Has no enamel. Has a foramen at its apical end through which vessels and nerves enter to supply the tooth.
25
enamel - where found, synthesized by and structure
crown only
ameloblasts which are lost after eruption
96-98%mineral content, chiefly hydroxyapatite – a calcium phosphate complex that is the inorganic constituent of bones and teeth
26
dentine (dentin) produced by, structure, special characteristics
odontoblasts
mineralised extracellular matrix similar to bone-approximately 70% mineral content, 30% organic components( including collagen fibres and mucopolysaccharide)
sensitive as holes which extend into pup cavity and cause transmission of pain - in horse not due to calcification process but if trim enough will be
no cells embedded in dentine
27
list and describe the different types of dentine
Primary – the outermost layer of dentine, is produced by the odontoblasts while they are located closest to the enamel layer during tooth formation befre eruption
- Secondary –Laid down slowly and results in narrowing of pulp cavity with age. In brachydont teeth is produced after root formation complete. In horse teeth prevents pulp exposure at occlusal surface arising from normal wear. After eruption - thickens and makes the cavity narrower - one that takes up stain from food
- Tertiary – Produced in response to injury or damage. May also be laid down in horse teeth to protect tip of pulp cavity from exposure.
28
cementum (cement) produced by, function and structure
cementoblasts some remain embedded
surrounds and protects dentine of root and anchors the periodontal ligament and alveolar bone
• In hypsodont teeth also contributes to bulk and strength of the crown
• not as readily degraded as bone (e.g. during orthodontic work)
• mineralised extracellular matrix similar to bone – approx 60-65% mineral content
29
dental pulp structure and things that lay within
connective tissue with abundant blood vessels, nerves - touch and pain both of which enter through apical foramen
superior and inferior alveolar arteries through jaws
superior maxillary branch of trigeminal nerve, inferior mandibular branch of trigeminal nerve
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