Connective Tissue and Articular Cartilage

Question 1

Type II collagen is found in

Answer 1

Hyaline cartilage. thinner than type I, lower tensile strength, provide framework, structure for other tissues

Question 2

Where is elastin found?

Answer 2

hyaline cartilage, ligamentum flavum

Question 3

GAGs are found in Ground Substance, have a ____charge and are Hydro_____

Answer 3

negative, philic

Question 4

What does the water provide in ground substance

Answer 4

diffusion of nutrients, provides mechanical properties

Question 5

Where are fibroblasts found?

Answer 5

ligaments, tendons, Supportive CTs

Question 6

Where are Chondrocytes found?

Answer 6

hyaline articular cartilage, fibrocartilage

Question 7

composition of dense connective tissue

Answer 7

HIGH type I collagen, LOW elastin and fibroblasts

Question 8

ligaments, tendons, and capsules are examples of

Answer 8

dense connective tissue

Question 9

These characteristics describe which type of tissue

Answer 9

poor healing (low vascularity), adapts to stress/strain with increased stiffness (increased collagen and GAG synthesis)

Question 10

Where is irregular dense connective tissue found?

Answer 10

joint capsule

Question 11

Which type of Dense connective tissue is resistant to tensile forces in MULTIPLE directions?

Answer 11

Irregular (joint capsule)

Question 12

how is collagen arranged in irregular dense connective tissue?

Answer 12

irregular in ground substance

Question 13

Which type of connective tissue is orderly and has a parallel arrangement of collagen?

Answer 13

Regular Dense Connective Tissue

Question 14

Which has more elastin? Ligament or Tendons

Answer 14

Tendons - transmit large forces from muscle to bone

Question 15

Regular dense connective tissue in ligaments and tendons resist tension along the _____ axis

Answer 15

longitudinal

Question 16

How long is the Inflammatory Phase of healing?

Answer 16

1-10 days

Question 17

How long is the Proliferation (consolidation) phase?

Answer 17

3-30 days

Question 18

How long is maturation (remodeling) phase

Answer 18

3-360 days

Question 19

Which phase of healing are neutrophils and macrophages active?

Answer 19

Inflammatory phase

Question 20

What is the body’s natural response to injury

Answer 20

inflammatory phase

Question 21

Connective Tissue is rebuilt with _____ tissue in the proliferation phase

Answer 21

granulation

Question 22

Fibroblasts are active in which phase of healing

Answer 22

proliferation

Question 23

In Maturation phase, collagen remodels from Type ___ to Type ___

Answer 23

III to I

Question 24

On a load-deformation curve, describe the plastic region

Answer 24

top of plateau to the ultimate failure point

Question 25

In Load-Deformation curve, what is the elastic region

Answer 25

the slope

Question 26

The yield point in the load deformation curve is where which two sections meet?

Answer 26

elastic and plastic

Question 27

In a stress strain curve, what is the area under the curve

Answer 27

energy

Question 28

the slope of elastic region in a stress strain curve is

Answer 28

stiffness

Question 29

Since biological materials are viscoelastic, there is a toe region. describe it

Answer 29

non linear region. before the elastic region

Question 30

When does viscoelastic creep occur

Answer 30

when exposed to a constant load

Question 31

What type of stretches are thought to bring on plastic changes to connective tissue

Answer 31

slow, low-intensity, and long-duration stretches

Question 32

What does the slope look like in the stress strain curve when we add a faster loading rate

Answer 32

steeper slope and increase stiffness

Question 33

Stress-relaxation is a stress response that occurs when exposed to a constant ______

Answer 33

deformation

Question 34

describe what is occurring when there is a high rapid high initial stress followd by a slow decreasing stress required to maintain the deformation

Answer 34

stress-relaxtion

Question 35

Name the type of collagen: thick, little elongation, stiff, strong, binds, supports bony articulation found in: ligaments, fibrous Joint capsules, tendons

Answer 35

Type 1

Question 36

The organic matrix of articular cartilage makes up 15-30% of the volume. What provides the structural framework?

Answer 36

Collagen (Type II) within proteoglycan solution

Question 37

List one function of articular cartilage

Answer 37

1. increase area of load distribution for joints 2. attenuate joint contact stresses 3. provide a smooth, wear resistant bearing surface

Question 38

What makes up the majority of the composition of articular cartilage?

Answer 38

water, salts, glycoproteins, lipids - 60-85% of volume Organic matrix - 15-30% chondrocytes - 10%

Question 39

Why is there a near frictionless behavior between joint surfaces?

Answer 39

synovial fluid

Question 40

Mechanical properties of Articular cartilage

Answer 40

high tensile stiffness and strength cannot resist compression well anisotropic - collagen fiber arrangement and densities vary bi-phasic material - fluid and solid

Question 41

Where is water concentrated in the articular cartilage?

Answer 41

near articular surface

Question 42

What does water permit in articular cartilage

Answer 42

exchange of gases nutrients and waste products between chondrocytes and synovial fluid

Question 43

What supports more than 90% of the applied load on a joint?

Answer 43

pressurization

Question 44

The magnitude of stress required to maintain the equilibrium displacement decreases over time. what definition is this?

Answer 44

stress-relaxation.

Question 45

What is shear stiffness of articular cartilage from.

Answer 45

collagen only, not interstitial fluid flow in pure shear

Question 46

What is the splitting of the cartilage surface called?

Answer 46

Fibrillation

Question 47

What happens to water content and permeability in the degeneration of articular cartilage?

Answer 47

they both increase

Question 48

Changes in collagen and PG content and structure Loosening of structure (increased permeability and fluid content) increased fluid flow and decreased ability to resist loading are all indicators of what?

Answer 48

osteoarthritis

Question 49

What are the three proposed mechanisms for the wearing out of cartilage?

Answer 49

1 - tensile failure of collagen fiber network- accumulated tissue damage leads to lower strength 2 - 'washout' of PGs from extracellular matrix from repeated fluid exudation resulting in decreased stiffness and increased permeability 3 - rapid application of high loads - no time for stress- relaxation ( fluid redistribution) resulting in high stresses that may cause damage

Question 50

An anatomical example of a 2nd class lever and explain why it's 2nd class.

Answer 50

The foot is an example of a 2nd class lever when in plantar flexion because the load (BW) is between internal force (calf muscles) and the fulcrum(ball of the foot)