Lecture 27 - Tissue Intro Flashcards
What are the 4 classes of connective tissue
1) Blood
2) Bone
3) Cartilage
4) Connective tissue proper
Connective tissue of all types is characterized by
1) Extracellular matrix
2) Cellular Component
T or F: Extracellular matrix and the cellular component determine the properties of tissue, but mainly the extracellular matrix
T
Extracellular Matrix is made of what 2 components
- Fibrillar component
- Interfibrillar component
What 2 things makes up the fibrillar component of the extracellular matrix
- Collagen
- Elastin
What 2 things makes up the interfibrillar component of the extracellular matrix
- Proteoglycans
- Glycoproteins
What cells make up the cellular component
Resident cells
What are 4 types of resident cells
1) Fibroblasts
2) Osteoblasts
3) Chondroblasts
4) Tenoblasts
Fibroblasts make
collagen
Osteoblasts make
Bone
Chondroblasts make
cartilage
Tenoblasts make
tendon
What are 4 characteristics of collagen
1) Provides functional integrity to connective tissue structures
2) Non-elastic
3) Most abundant protein in body
4) White fibrous tissue
Crimping
Orientation of collagen that allows elongation of the fibers before tensile stresses are experienced
What are the 3 types of collagen
1) Type I
2) Type II
3) Type III
Type I Collagen
Found in all connective tissue (most common) that resists tensile forces
Type II Collagen
Found in hyaline cartilage and intervertebral discs that resist compressive and shear forces
Type III Collagen
Found in skin, joint capsules, muscles, and tendon sheath that are used for healing/repair
3 characteristics of elastin
1) Yellow fibrous tissue
2) Elastic
3) Resist tensile forces, but have more give when elongated
Proteoglycans
Found mainly in connective tissue that affect hydration of the tissue
Describe the stress strain curve
What is viscoelasticity
Combined properties of viscosity and elasticity
Elasticity
Ability to return to original length/shape after removal of load
What does elasticity of a tissue depend on
elastin and collagen content and organization
Viscosity
Resistance to flow
What does viscosity depend on
proteoglycan and water composition of tissue
What 2 types of loading cause viscoelastic materials to undergo deformation
1) Tensile
2) Compressive
What are 4 viscoelastic characteristics
- Creep
- Stress-relaxation
3) Hysteresis
4) Strain-rate sensitivity
Creep
Phenomenon in which tissue will deform over time under constant load
Stress-Relaxation
Tissue stretched to constant length
Hysteresis
When a tissue is repeatedly loaded and unloaded, some energy is dissipated through tissue elongation and energy loss
Strain-Rate Sensitivity
Mechanical behavior is different depending if structure loaded rapidly or slowly