Teeth and Pancreas Flashcards
Which cells are involved in the formation of enamel and where are they located?
ameloblasts- located on dentin during tooth development.
What proteins are secreted during the formation of enamel?
Amelogenin (90%) and enamelin.
What happens to most of the proteins after they are secreted in tooth development?
They are mineralized by Ca and P.
What is the main component of enamel?
Calcium and phosphate crystals.
What is the structure and orientation of enamel rods?
Highly organized prisms.
Each rod is produced by an ameloblast.
Which cells are involved in the formation of dentin and where are they located?
Odontoblasts- located in pulp cavity, and produce predentin (unmineralized matrix).
What is difference between detin and predentin?
Predentin- Unmineralized organic matrix
Dentin- Mineralized
What makes up dentin?
- Type I collagen
- Ground substance (glycosaminoglycans)
- Hydroxyapatite crystals (more than bone, so harder than bone)
Describe the formation, structure, location and function of odontoblastic processes:
Formed: by odontoblast retreat
Structure: sting-like
Location: Dentinal tubule
Function: transmit stimuli from tooth surface to nerve.
Describe the components of tooth pulp:
- Blood vessels
- Collagen
- Fibroblasts
- Immune cells
- Odontoblasts
- Pain nerve fibers
How does the tooth stay in the socket?
Peridontium- tissues involved in attachment of tooth to bone.
Which section of gingina contains stratified squamous keratinized?
Free gingiva.
Which sections of gingiva contain non-keratinized stratified squamous?
Sulcular epithelium- not firmly attached.
JE- firmly attached.
What helps join the JE to the tooth?
A. Desmosomes
B. Hemidesmosomes
B. Hemidesmosomes
Describe the location and structure of cementum:
Surrounds dentin in the root area of the tooth.
Similar to bone.
Made by cementoblasts.
Which cells in the periodontal ligament produce the ground substance and type I collagen fibers? A. Osteoblasts B. Osteoclasts C. Cementoblasts D. Fibroblasts E. Immune cells
D. Fibroblasts
Besides connecting bone to cementum, what are the other functions of the PDL?
- Shock absorber
- Sensory (nerve endings)
- Nutritive function (blood supply)
- Remodeling function (mesenchymal cells differentiate)
PDL structure:
Connects alveolar bone to cementum via Sharpey’s fibers (type I collagen).
What is the role of the blood supply and nerve endings in the periodontal ligament?
Nutrition
Sensory
Describe the general organizational structure of the pancreas:
- Capsule surrounding lobules with many septa (CT) running through it.
- Contains blood vessels and interlobular ducts.
How can you tell the difference between a vein, artery and duct?
Ducts- cuboidal, stain darker.
A/V- Simple squamous
Are pancreatic acini the endocrine or exocrine part of the pancreas?
Exocrine- secrete their substances into a duct.
What do centroacinar cells secrete and where are they located?
Located in an acinus near the intercalated duct.
Secrete bicarb.
What are the secretions of pancreatic acinar glands?
Bicarb Zymogen granules (inactive protease)- prevents digestion of cellular proteins.
How can you positively identify a section as endocrine pancreas?
Islets of Langerhans
What are the other digestive enzymes secreted by the pancreas?
- lipase (lipids)
- amylase (carbs)
