Oral Cavity - Hard And Soft Palate Flashcards
(23 cards)
What parts of the oral cavity is made of soft tissue?
- Pulp
- Oral mucosa
What parts of the oral cavity is made of hard tissue?
- Teeth
- Bone
What is the border where the lips meet the oral mucosa?
Vermillion border
Whats the organisation of the oral mucosa?
Stratified squamous epithelia (top layer) - can be keratinised or not
Basement membrane (bottom layer)
Lamina proper
Submucosa
What are the different types of keratinisation?
- Orthokeratinised = no nucli at the surface layer only keratin
- Parakeratinised = nuclei retained but still has keratin eat surface layer
- Non-keratinised - = No keratin layer
What is the difference between simple and stratified epithelium?
Simple - Single layer = normally used for gases or fluid exchange
Stratified - more than 2 layers = normal has a protective function
What does endothelium mean?
Epithelium has blood vessels
What is pseudostratified ciliated columnar epithelium?
Have cillia on the top surface, usually found in respiratory lining e.g lungs
What factors effect connective tissue?
- Tensile strength - provided by structural proteins e.g. collagen
- Elasticity - provided by elastin fibres
- Volume - provide shake absorption e.g. glycoproteins
What is the connective tissue extra cellular martix? Where is it secreted from?
Fibres (elastin and collagen), ground substance (provide volume e..g glycoproteins) make up the extra cellular matrix
ECM
ECM is secreted from Fibroblasts
What is the difference between connective tissue proper and supporting connective tissue?
- Conective tissue proper has both ECM fibres and ground substance
- supporting connective tissue is mainly fibres and less cell content
What is ground substance?
- Highly hydrates substance with a mixture of macromolecules
- Fills space between fibres and act as shock absorbers
- Regulate the cells water content and diffusion
Contain proteoglycans and glycoproteins these are produced by fibroblasts
What are proteoglycans?
An extra cellular protein
- Found in ground substance
- Bind to water, acts as a growth factor and a cytokine
How do cell bind to the ECM?
Cell can bind to the collagen in the fibres so need a link, the link is Fibronectin
The glycoproteins adhere to the Fibronectin
What is Fibronectin?
Molecule that is on ECM structures to bind the cells to the ECM fibres
How many types of collagen are there?
7
What is elastin? Where is it made?
Made by the fibroblasts as tropoelastin and the Elastin polymer is made in the EMC
Elastin provides elasticity and allows the tissue to recover in shape if deformed
What are the 5 type of cell adhesions?
- Tight junctions
- Adherens junctions
- Desmosomes
- Gap junctions
- Hemidesmosome
What is an Adherens junction?
Helps in cell-cell anchoring
Important in cellular signalling as it interacts with the cytoskeleton
What are tight junctions?
When the 2 outer membranes of adjacent cells fuse, this forms a barrier and substances can’t pass through cells, solute can pass through the epithelial cell layer
What are Desmosomes?
Found in tissue with mechanical stress as the filament junctions provide strength so cells aren’t forced apart
- On the inner surface of the cells there is ‘plaque’ formed by glycoproteins and this extends fibres (cadherins) that anchor the cell providing the strength
What are Hemidesmosomes?
Attach the epithelial layer to the basement membrane
What are gap junctions?
- Found in smooth muscle and heart, they allow them to contact as a unit
Adjacent cells are connected by a hollow membrane proteins forming a channel when ions and small molecules move between the cells
The channel is called a Connexon and is made of 6 smaller connexins
