DHE119 chapter2 Quiz2

smallest structural unit of living matter functioning independently

• mesh-like material that holds cells and tissues together
• Made of gel-like substance and fibers
• active structure of molecules secreted by cells that provides structural and biochemical support to surrounding
• a component of all living tissues.

scanty –thin mat- basal lamina –underlies epithelium

• STRATIFIED SQUAMOUS EPITHELIUM
• Flat cells arranged in layers

closely packed epithelial cells bound together in sheets - rest on connective tissue

small, thin mat under cellular sheets

process by which epithelial cells on the surface of the skin become stronger and waterproof

• no nuclei
• Most heavily keratinized epithelium of body is on palms of hands and soles of feet

• have nuclei
• Cushion mechanical stress and wear
• Softer -More flexible
• Mucosal lining of cheeks:
• Permits movement needed to speak, chew, and make expressions
• Non-keratinized surfaces must be kept moist by bodily secretions to prevent them from drying out

• Permits movement needed to speak, chew, and make expressions
• Non-keratinized surfaces must be kept moist by bodily secretions to prevent them from drying out

• Cellular structures that mechanically attach a cell and its cytoskeleton to:
• Neighboring cells
• Basal lamina

• Allows cells to bind together -stronger structural unit
• SKIN-Epithelium that must withstand severe mechanical stresses have the most number of cell junctions

• connects two neighboring epithelial cells
• Think of snaps on a jacket

connects epithelial cells to basal lamina

Fills spaces between tissues and body organs

Main component in matrix is gel-like substance with a network of strong fibers

CT CELLS-sparsely distributed in extracellular matrix

cells that synthesizes the extracellular matrix and collagen, is the structural framework (stroma) for tissues, and plays a critical role in wound healing.

• Phagocytes (Cell Eaters-PAC MAN) 
• devour dying cells- invasive microorganisms

Cells- immune system

• CEMENTUM, DENTIN, PULP, ALVEOLAR BONE
• Enamel is epithelial tissue

reduced enamel epithelium

• the boundary where the epithelial and connective tissue meet.
• Wavy or smooth

• Epithelial ridges: Deep extensions of epithelium reach down into connective tissue
• Connective tissue papillae: Finger-like connective tissue extensions reach up to epithelium

• Enhances adhesion of epithelial tissue and connective tissue by increasing surface area of junction between two tissues.
• Epithelium receive nourishment from CT.
• Epithelium doesn’t have it's own Blood Supply
• Strong junction allows skin to resist mechanical forces

• STRATIFIED SQUAMOUS EPITHELIUM
• Functions well in wet environment of oral cavity
• Anatomy is similar to that of skin

1.Oral epithelium

2.Sulcular epithelium

3.Junctional epithelium

• Covers outer surface- free gingiva/ attached gingiva
• Located from the Crest of gingival margin to mucogingival junction
• Keratinized/ Parakertinized(partially keratinized)
• Interface-connective tissue- Wavy

• Epithelial lining of gingival sulcus
• Extends from crest of gingival margin to coronal edge of junctional epithelium
• Thin and nonkeratinized 
• Permeable Fluid flows from connective tissue to sulcus
• Smooth interface with connective tissue

• Forms the base of sulcus
• Joins gingiva to tooth
• More Cells Apical than coronal
• 15 to 30 cells thick in coronal zone
• Four to five cells thick in apical zone
• Thin and nonkeratinized
• Easiest point of entry for bacteria to invade connective tissue
• Smooth tissue interface with connective tissue

Thin basal lamina Between epithelial cells of junctional epithelium and tooth

Thin basal lamina Between epithelial cells of junctional epithelium and gingival connective tissue

• Forms immediately on a clean tooth surface
• Protective by diffusing acid
• Enables microbial attachment in early stages of biofilm formation
• Lies between tooth and internal basal lamina
• Also known as dental cuticle or acquired pellicle 
• Forms during late stages of tooth eruption

• Attaches to tooth surface using hemidesmosomes and internal basal lamina
• Cells of the junctional epithelium can move along the tooth surface

• Attaches using hemidesmosomes and external basal lamina
• Healthy junctional epithelium has a smooth tissue interface with connective tissue

• Provides a seal at base of gingival sulcus or periodontal pocket
• Provides a protective barrier between plaque and connective tissue

• Provides solidity to gingiva
• Attaches gingiva to cementum of root and bone

• Few cells (5%):
•   Fibroblasts, neutrophils, macrophages, lymphocytes
• Abundant extracellular matrix:
•  55% to 65% protein fibers (collagen)
• 30% to 35% gel-like matrix

Rope-like collagen fiber bundles located coronal to alveolar crest

• Embedded in extracellular matrix
• Junctional epithelium attachment to tooth is strengthened by fiber bundles
• Provides structural support to gingival tissues

• Brace free gingiva firmly against tooth
• Reinforce attachment of junctional epithelium to tooth
• Provide free gingiva rigidity to withstand chewing
• Unite free gingiva with cementum of root and boneConnect adjacent teeth to each other

• Alveologingival
• Circular
• Dentogingival
• Periostogingival
• Intergingival
• Intercircular
• Interpapillary
• Transgingival
• Transeptal