Digestive System Histology

Question 1

Acini cells are drained by what?

Answer 1

Acini are drained by intercalated ducts.

Question 2

List the 3 types of acini

Answer 2

Mucus acinus
Serious acinus
Mixed acinus

Question 3

What is the name given to Serous acinus cells on the mixed acinus?

Answer 3

Serious demilunes and crescents of Gianuzzi

Question 4

What is another name of the mixed acinus

Answer 4

Mucous acinus

Question 5

What is the function of the caps of serious cells on the mucous acinus?

Answer 5

They attach the mucous producing acini and empty their secretions into interstices between the mucous producing cells

Question 6

What is the function of the salivary glands?

Answer 6

They produce saliva and pour their secretion into the the oral cavity through ducts.

Question 7

What components make up the digestive system?

Answer 7

Mouth
Pharynx
Esophagus
Stomach
Small intestine
Large intestine

Question 8

What are the accessory organs of the digestive system?

Answer 8

Gall bladder
Liver
Pancreas
Salivary glands

Question 9

What are the accessory organs of the digestive system located in the mouth?

Answer 9

Teeth
Tongue

Question 10

How does the location of the myoepithelial cells aid in its function?

Answer 10

It is located between the basement membrane and epithelial cells. These cells squeeze out secretions..

Question 11

What are the two types of intralobular ducts of the salivary gland?

Answer 11

Striated ducts
Intercalated ducts

Question 12

List some differences of the mucous acinus and serious acinus.

Answer 12

Mucous acinus Serious acinus
Oval structure Spherical structure
Lined with columnar cells Lined w/ columnar and pyramidal cells
Has a flat nucleus on situated the basement membrane Have a round nucleus situated on the basal line
Has a large lumen Has a small lumen
Secretory granules located on the apex Secretory granules located on apical part of the acinus

Question 13

What is the function of intercalated ducts and what are they lined by?

Answer 13

Intercalated ducts drain the acini and they are lined by simple cubodial epithelium

Question 14

Describe striated ducts

Answer 14

These ducts are formed by the intercalated ducts and lined by simple columnar epithelium.

Question 15

Describe the interlobular ducts.

Answer 15

These ducts are embedded in the connective tissue surrounding the lobules of the salivary glands and are lined with striated cuboidal and columnar epithelium.

Question 16

The lobules of the mucous salivary glands contains what?

Answer 16

Mucous acinus

Question 17

Describe the composition of the mixed salivary gland.

Answer 17

Consist of lobules mainly of serious acini and also groups of mixed acini

Question 18

Describe the 2 layers of Mucosa (mucous membrane) as it relates to the tongue.

Answer 18

The outer epithelium consist of stratified squamous non keratinized type and is keratinized over the papillae.
The inner lamina propria consist of the blood vessels, serious and mucus glands and connective tissue

Question 19

What are papillae and what is it made up of?

Answer 19

Papillae are projections of the mucosa and covered by epithelium.
The core of the papillae are made of lamina propria and corium.

Question 20

Compare and contract the filiform, fungi form and circum vallate papillae.

Answer 20

Filiform papillae:
small conical projections covered by horny keratinized cap. No taste buds. All over the dorsum of anterior 2/3 of tongue. Stratified squamous keratinized epithelium.

Fungiform papillae - has rounded top and narrow base. Has taste buds. Located at the apex and lie along the lateral margin on the anterior 2/3 of the dorsium on tongue. Stratified squamous epithelium.

Circum vallate papillae - largest papilla. 8-12 in numbers. Round top, narrow bottom. Has taste buds that lines its lateral wall. Is surrounded by a circular sulcus. The sulcus receives the opening ducts of the serious glands. Serious secretion of these glands distributes the substance to be tasted and wash off the debris in the sulcus. Stratified squamous non- keratinized epithelium.

Question 21

What are the 4 layers of the alimentary canal

Answer 21

Mucosa, Submucosa, muscularis externa, serosa.

Question 22

Give another name for the mucous membrane.

Answer 22

Mucosa.

Question 23

Describe the composition of the lamina propria and muscularis mucousa.

Answer 23

Lamina propria is made up of loose areiolar connective tissue, has glands, lymph vessels and occasionally lymph nodes.
Muscularis mucosa is made up of inner circular layer and outer longitudinal layer of smooth muscles.

Question 24

What are the features of the Submucosa of the GI tract?

Answer 24

They consist of irregular fibroelastic connective tissue and has elastic and collagen fibers.
Has no glands except only in the esophagus and duodenum
Meissner’s or submucosal plexus of nerves.

Question 25

What are the features of the Muscularis externa?

Answer 25

Compromised of inner circular and outer longitudinal layers of smooth muscles. Auerbach’ or myenteric plexus of nerves are situated between the two layers of smooth muscles and regulates the activity of the muscularis externa.

Question 26

What’s the difference between the serosa and adventitia?

Answer 26

The serosa is the term used to describe the connective tissue layer that surrounds the muscularis externa in the gastrointestinal tract Adventitia is the term to describe the connective tissue layer that surrounds the muscularis externa in the esophagus and duodenum.

Question 27

List the four layers of the esophagus

Answer 27

Mucosa Submucosa Muscularis externa Adeventitia

Question 28

Describe the epithelium of the esophagus.

Answer 28

The epithelium for most part of the esophagus is made up of stratified squamous non- keratinized type. The epithelium at the lower part of the esophagus is made up of simple columnar type epithelium.

Question 29

Describe the histology of the muscularis externa in the esophagus.

Answer 29

It’s is composed of inner circular layers and outer longitudinal layers of smooth muscle fibres. The top layer of the muscularis externa is composed of skeletal muscle, the middle layer is skeletal and smooth muscles and the bottom layer is smooth muscles.

Question 30

What is the function of the Submucosa glands in the esophagus?

Answer 30

The Submucosa glands are responsible for producing or secreting mucus to aid in the passage of food.

Question 31

List the four parts of the stomach.

Answer 31

Cardia Fundus Body Pyloric part

Question 32

List the four parts of the cardia of the stomach

Answer 32

Mucosa Submucosa Muscularis externia Serosa

Question 33

What are tubular cardiac glands?

Answer 33

Glands located in the cardiac mucosa that that joins with the gastric pits. These glands secrete mucus to protect the esophagus from gastric reflux It is also apart of the stomach gastric juice.