Topic 15: Digestive System - Teeth, esophagus

Question 1

What are the 5 parts of a tooth?

Answer 1

1. crown
2. root
3. neck
4. periodontal ligaments
5. root canal extending to pulp cavity

Question 2

What is the crown? (3)

Answer 2

• above the gum
• dentin = majority of tooth
• enamel overlay

Question 3

What is enamel? (2)

Answer 3

• acellular
• highly calcified - hard!

Question 4

What is the root composed of? (2)

Answer 4

• dentin and cementum overlay
• it is dentin, enamel, cementum

Question 5

What is the root similar to?

Answer 5

• similar to bone, but avascular

Question 6

What does the neck of the tooth include?

Answer 6

• enamel + cementum boundary (at gums)

Question 7

What do the periodontal ligaments attach?

Answer 7

attaches root to bone

Question 8

What does the root canal. which extends to the pulp cavity, contain? (3)

Answer 8

• CT
• Blood/lymph vessels
• nerves

Question 9

What is the oropharynx and laryngopharynx made of? (2)

Answer 9

• only muscularis externa (skeletal muscle)
• stratified squamous epithelium

Question 10

Where is the esophagus?

Answer 10

• posterior to trachea
• passes through diaphragm to the abdominal cavity

Question 11

After the esophagus passes through to the abdominal cavity, what histologic layers are after this?

Answer 11

• all 4 layers in GI tract after this

Question 12

What are 2 exception to the esophagus histology?

Answer 12

• muscularis externa
• has adventitia

Question 13

Name the 3 parts of the muscularis externa in which are exceptions to the esophagus histology/

Answer 13

upper 1/3 = skeletal muscle
middle 1/3 = skeletal + smooth
lower 1/3 = smooth muscle

Question 14

What type of adventitia is in the esophagus?

Answer 14

fibrous CT (no epithelium)