Digestive Histo I

Question 1

Name the associated/accessory digestive organs and whether they are responsible for physical breakdown (PB) or secretions (S).

Answer 1

Tongue (PB), teeth (PB), salivary glands (S), Pancreas (S), liver (S), and gallbladder (S)

Question 2

What percentage of absorption occurs in the SI?

Answer 2

90%

Question 3

What is the skeletal muscle that surrounds the opening of the oral cavity?

Answer 3

Orbicularis oris

Question 4

What is the term for the opening of the oral cavity into the oropharynx?

Answer 4

Fauces

Question 5

What is the vestibule?

Answer 5

The area between the lips/teeth and the cheeks/teeth; oral cavity proper is the rest of the area of the oral cavity before the fauces

Question 6

What type of cells line the oropharynx and laryngopharynx?

Answer 6

Nonneratinized stratified squamous

Question 7

What are the layers of the alimentary canal going from the lumen outward?

Answer 7

1.Mucosa 2.Submucose 3.Muscularis externa 4.Serosa/Adventitia

Question 8

What are the layers of the mucosa from lumen outward?

Answer 8

1.Lining epithelium 2.Lamina propria 3.Muscularis Mucosae

Question 9

What are the layers of the Muscularis externa?

Answer 9

1.(Inner) circular muscle 2.(External) Longitudinal muscle

Question 10

What are the serosa/adventitia layers?

Answer 10

1.Areolar CT (inner) 2. Epithelium (outer)

Question 11

Which organs are highly associated with having simple columnar lining epithelium?

Answer 11

Stomach, SI, and most of LI

Question 12

Which layer of the mucosa contains blood vessels?

Answer 12

The lamina propria

Question 13

What is GALT and where is it located?

Answer 13

Gut-Associated Lymphatic Tissue; lamina propria

Question 14

Which of the alimentary canal layers contains glands, some lymphoid tissue, and Meissner’s plexus?

Answer 14

Submucosa

Question 15

What is responsible for controlling the secretion of lining epithelium?

Answer 15

Meissner’s plexus

Question 16

Which smooth muscle layer can be thickened to form sphincters or valves?

Answer 16

The inner circular layer of the muscularis externa

Question 17

Contraction of this muscle constricts the lumen and lengthens the organ?

Answer 17

Inner circular smooth muscle; outer longitudinal does the opposite

Question 18

What is responsible for the alternating contraction of inner circular and outer longitudinal layers?

Answer 18

The myenteric (Auerbach’s) plexus; this plexus is located between inner circular and outer longitudinal layers

Question 19

What kind of CT makes up the submucosa?

Answer 19

Dense irregular CT

Question 20

Describe the difference in type of muscle (skeletal or smooth) of the muscularis externa of the esophagus.

Answer 20

Upper 1/3 = skeletal, middle 1/3 = mixed skeletal and smooth, lower 1/3 = smooth

Question 21

Which type of esophageal glands are found in the submucosa closer to the stomach and what do they produce?

Answer 21

Esophageal cardiac glands; mucous, important to protect esophagus from acid reflux from the stomach