Digestive System II

Question 1

Salivary glands

Answer 1

• open into oral cavity

- receive both sympathetic (thick saliva) and parasympathetic (watery saliva) innervation

Question 2

Minor salivary gland

Answer 2

• scattered in submucosa of oral cavity

- named for location (lingual, buccal, labial, pharyngeal, palatine)

Question 3

Major salivary gland

Answer 3

• compound gland
• encapsulated with thin septa between lobules
• typically tubuloacinar organization

Question 4

What type of secretion does the parotid salivary gland have?

Answer 4

predominately serous secretion

Question 5

What glands have mixed serous and mucous secretion?

Answer 5

mandibular
sublingual
zygomatic
molar (buccal)

Question 6

What do serous cells form?

Answer 6

acini or demilunes, which cap mucous acini

Question 7

What do mucous cells form?

Answer 7

acini or tubuloacinar units

Question 8

What surrounds both acini and intercalated ducts?

Answer 8

myoepithelial cell processes

contraction of cell processes helps move secretions along the duct system

Question 9

Duct system of salivary glands is branched or unbranched?

Answer 9

branched

Question 10

What 2 types of interlobular secretory ducts secrete H2O and electrolytes?

Answer 10

intercalated ducts

striated ducts

Question 11

Intercalated ducts

Answer 11

• very short and inconspicuous

- arise directly from the acini

Question 12

Striated ducts

Answer 12

• continuous with the intercalated ducts

- striations are a result of basal mitochondria aligned between membrane infoldings

Question 13

Name the 2 ducts of the excretory duct system

Answer 13

interlobular duct

main duct

Question 14

Where do main ducts open to?

Answer 14

oral cavity

Question 15

Name the 6 functions of the salivary glands

Answer 15

1. protection of the oral cavity and teeth
2. production of lubricant for dry ingesta
3. provide fluid for rumen and pH adjustment
4. source of IgA from adjacent plasma cells and perhaps hormones
5. production of digestive enzymes
6. regulation of electrolyte balance

Question 16

Name the 3 types of salivary glands (i.e. what do they secrete?)

Answer 16

mucous
serous
mixed

Question 17

4 functions of the GI tract

Answer 17

1. movement of ingesta through the tube
2. digestion (mechanical and chemical)
3. absorption of simple nutrients
4. secretion of enzymes, hormones, and mucin

Question 18

Name the 7 layers of the GI tract, from lumen to outside

Answer 18

1. lamina propria
2. muscularis mucosae
3. tunica mucosa
4. tunica submucosa
5. tunica muscularis (inner)
6. tunica muscularis (outer)
7. tunica serosa

Question 19

How many muscularis mucosae layers can there be in the GI tract?

Answer 19

0-3 layers

Question 20

Where are mucosal glands found in the GI tract?

Answer 20

from glandular stomach through rectum

Question 21

Submucosal nerve plexus

Answer 21

a bundle of nerves in the tunica submucosa that contains sympathetic and parasympathetic fibers

Question 22

What are the 2 layers of the tunic muscular is?

Answer 22

inner circular muscle layer

outer longitudinal muscle layer

Question 23

What does the inner circular muscle layer of the tunica muscularis form?

Answer 23

sphincters

Question 24

What does the outer longitudinal muscle layer of the tunica muscularis form?

Answer 24

longitudinal bands (tenia)

Question 25

Esophagus

Answer 25

highly distensible organ due to longitudinal folds and elastic fibers

Question 26

Striated muscle in esophagus

Answer 26

- found along entire length of esophagus in dog and ruminant | - found cranially only in cat, pig, and horse

Question 27

3 functions of the simple glandular stomach

Answer 27

1. storage and mixing 2. mechanical and chemical digestion 3. secretion of mucous, enzymes, H20, electrolytes, and hormones

Question 28

3 gastric gland regions of the simple stomach

Answer 28

1. cardiac gland region 2. pyloric gland region 3. fundic gland region

Question 29

Characteristics of the cardiac gland region

Answer 29

- found near esophagus, may be small - contains mucous cells - pits and glands may be short and have wide lumen

Question 30

Characteristics of the pyloric gland region

Answer 30

- near pyloris - contains mucous cells - deepest pits and short, coiled glands - thickest T. muscularis

Question 31

Characteristics of fundic gland region

Answer 31

- body and fundus of stomach - largest region - greatest variety of cell types in glands

Question 32

Gastric glands

Answer 32

simple branched or coiled tubular, fill the lamina propria

Question 33

Where is the subglandular layer of the stomach?

Answer 33

between the lamina propria and the muscularis mucosae

Question 34

What 2 parts make up the subglandular layer?

Answer 34

``` stratum granulosum (very cellular) stratum compactum (packed collagen fibers) ```

Question 35

3 layers of the tunica muscularis in the stomach

Answer 35

1. inner oblique 2. middle circular (gives rise to sphincters) 3. outer longitudinal layer