Digestive system I

Question 1

What are the 4 main layers of the GI tract?

Answer 1

Tunica mucosa
Tunica submucosa
Tunica muscularis
Tunica serosa

Question 2

Describe the Tunica Mucosa

Answer 2

Innermost layer

Question 3

What are the 3 layers of the Tunica mucosa?

Answer 3

Epithelial lining
Lamina propria
Muscularis mucosae

Question 4

Describe the Tunica submucosa

Answer 4

Contains glands & lymphatic tissue, blood vessels, irregular connective tissue, Miesser nerve plexus

Question 5

Describe the Tunica muscularis

Answer 5

2 or more layers of smooth muscle (circular & longitudinal)

Question 6

Does the Tunica muscularis have nerves?

Answer 6

Yes, myenteric plexus located in the connective tissue between the 2 muscle layers

Question 7

What 2 plexuses form the ENS?

Answer 7

Myenteric & Miessners

Question 8

Describe the Tunica Serosa

Answer 8

Mesothelium

Made of simple squamous epithelium

Question 9

When is Tunica serosa used vs Tunica adventitia?

Answer 9

Serosa: intraperitoneal organs
Adventitia: retroperitoneal organs

Question 10

What are the 3 surfaces of the lips?

Answer 10

Skin
Oral mucosa
Muco-cutaneous junction

Question 11

What is the difference between oral mucosa in pigs and ruminants?

Answer 11

Ruminants have keratinized oral mucosa

Question 12

What type of muscle is present in the core of the lips?

Answer 12

Skeletal muscle

Question 13

WHat is the hard palate? What is the epithelium covering it?

Answer 13

Bony roof of the mouth

Covered by keratinized stratified squamous epithelium

Question 14

What are dental pads?

Answer 14

Heavily keratinized hard palates in ruminants

Question 15

What is the soft palate?

Answer 15

Separates oral cavity from nasopharynx

Question 16

How are tongue muscle fibers oriented?

Answer 16

In all directions

Question 17

What is the lyssa of the tongue?

Answer 17

Cord-like structure that extends on ventral mid-line

Question 18

What are the 4 types of tongue papillae?

Answer 18

Filiform
Fungiform
Vallate
Foliate

Question 19

Which tongue papillae does not have gustatory receptors?

Answer 19

Filiform

Question 20

Which tongue papillae are most heavily keratinized?

Answer 20

Filiform

Question 21

What are Ebner’s glands?

Answer 21

Gustatory glands located in the sulcus of foliate papillae

Question 22

Which is the largest tongue papillae?

Answer 22

Vallate

Question 23

What is the vallate papillae surrounded by?

Answer 23

Deep furrow

Question 24

Where are taste buds located on the vallate papillae?

Answer 24

Lateral side opening in to sulcus

Question 25

What are the 3 cell types associated with taste buds?

Answer 25

Sustentacular cells Gustatory cells Basal cells

Question 26

What is the purpose of sustentacular cells?

Answer 26

Support

Question 27

What is the purpose of basal cells?

Answer 27

Stem cells

Question 28

What are "taste hairs"?

Answer 28

Microvilli that extend in to taste pore

Question 29

``` What flavor do sodium ions create? Hydrogen ions? Sugars? Alkaloids? Amino acids? ```

Answer 29

``` Salty Sour Sweet Bitter Umami ```

Question 30

Which types of animals have bracydont teeth? Hypsodont?

Answer 30

Carnivores | Herbivores

Question 31

Do brachydont teeth continue growing after eruption?

Answer 31

No

Question 32

WHat are the areas of the brachydont? DO hypsodont teeth have these areas?

Answer 32

Crown Neck Root No

Question 33

What is the hardest component of the human body?

Answer 33

Enamel (96% hydroxyapatite)

Question 34

What cells secrete enamel?

Answer 34

Ameloblasts

Question 35

Does enamel contain collagen?

Answer 35

No

Question 36

What secretes dentin? Is collagen present in dentin?

Answer 36

Odontoblasts | Yes

Question 37

What secretes cementum? Does it contain collagen?

Answer 37

Cementoblasts | Yes

Question 38

WHat leads to periodontal disease?

Answer 38

build up of tartar

Question 39

Describe steps of tooth development

Answer 39

``` thickening of mesenchyme bud cap bell erupted tooth ```

Question 40

What is the dental lamina?

Answer 40

Stage I development: oral epithelium invades mesenchyme

Question 41

What is the tooth bud?

Answer 41

Stage II development: dental lamina forms epithelial bulge

Question 42

What is the enamel organ?

Answer 42

Stage III development: tooth bud increases in size and forms cap

Question 43

What is the bell?

Answer 43

Stage IV development: cap is converted to bell by epithelium and papillary mesenchyme growth

Question 44

Everything that forms the tooth comes from the mesenchyme except what?

Answer 44

Enamel comes from enamel organ