Anatomy I: Cartilage

avascular,

not innervated,

no lymph vessels

What are the characteristics of cartilage?

-vascular vs avascular

-innervated vs non-innervated

-presence of lymph vessels?

Collagen Type II

What is the main type of collagen in cartilage?

Perichondrium

What surrounds cartilage?

isolated cells surrounded by a matrix

How do you physically describe cartilage?

irregular dense CT

What is perichondrium made of?

By its extracellular matrix and its high content of glycoaminoglycans and protegoglycans

How is cartilage characterized by?

Brings and retains water which makes it resistant to compression

What do glycoasminoglycans provide for cartilage?

Chondroblasts: border the perichondrium

Condrocytes: fully differentiated and contained within lacunae

What are the two types of cells for cartilage?

Collagen type II

Elastic fibers (depends on type)

What are the fibers present in collagen?

1. Proteoglycans

2. Glycosaminoglycans

3. Hyaluronic acid

What is in the extracellular matrix of collagen?

1. Bear mechanical stress

2. Form a framework to support soft tissue

3. Shock absorption

4. Provides sliding on joint movement

5. Bone development

What are the functions of cartilage?

1. Harbor vascular supply

2. Nutrition by diffusion through blood vessels

3. Chondrogenic

4. Attachment to muscles and tendons

What is the function of perichondrium?

articular cartilage

What type of cartilage does not have perichondrium?

Tissue=Perichondrium

A: outer fibrous layer: more fibers than cells

B: inner cellular layer: more cells than fibers

What is A and B and what is the difference between the layers?

hyalin cartilage (not very many fibers present)

What type of tissue is this?

protection

What is the function of the outer fibrous layer of pericondrium?

chondrogenic (contains chondroblasts, flat cells with flat nuclei)

What is the function of the inner cellular layer of pericondrium?

Young: elliptical

Mature: round

What shape are young vs mature chondrocytes?

Cortisone and estradiol

What hormones inhibit chondrocytes function?

GH, thyroid hormones, and testosterone

*testosterone is why old men have big ears

Which hormones accelerate glycosaminoglycan synthesis?

Cluster of chondrocytes enclosed by territorial matrix and separated from each other by a more expansive and plate interterritorial matrix

What is an isogenic group?

A: interterritorial

B. Territorial

Identify the type of matrix indicated by A and B.

Apppsitional

What type of cartilage growth occurs from growth on the outside?

Interstital

What type of cartilage growth occurs from growth from within?

appositional

What type of growth occurs in the perichondrium when the condroblasts secrete matrix and differentiate into condrocytes?

intersitital

What type of growth occurs when condryoctes divide and secrete new matrix making isogenic groups?

- no collagen change

- less efficient in renewing matrix -> less proteoglycans -> reduction in water -> less resistant to compressive = more vulnerable to weight-bearing injuries

How does cartilage change in aging?

hyaline cartilage

What type of cartilage?

Elastic cartilage

What type of cartilage?

Fibrocartilage

What type of cartilage?

Type II

What collagen is in hyaline cartilage?

Hyaline cartilage

What is the most common of the cartilage?

1. Support and Flexibility

2. Cushioning

3. Resists compressoin

4. In embryo, hyaline cartilage forms temporary skeleton

What are the functions of hyaline cartilage?

1. Connects ribs to the sternum

2. Larynx, trachea (respiratory)

3. Nasal

Where is hyaline cartilage found?

articular cartilage because it does not have the perichondrium

Which cartilage has the least capacity for repair?

Smooth lubricated surface for articulation

What is the function of articular cartilage?

Ends of long bones

Where is articular cartilage found?

parallel

What is the structure of collagen fibers on a sliding surface?

perpendicular

What is the structure of collagen fibers on a connecting surface?

integrins

What component of the matrix connects to the neighboring cells?

elastic cartilage

Which cartilage is rich in elastic fibers?

Collagen type II

What type of collagen fibers does elastic cartilage have?

maintains the shape of a structure while being flexible

What is the function of elastic cartilage?

external ear and epiglottis

What is the location of elastic cartilage?

Type I

What type of collagen is fibrocartilage made of?

1. Intervertebral discs

2. Pubic symphysis

3. TMJ

What is the location of fibrocartilage?

Strength with the ability to absorb compressive shock

What is the function of fibrocartilage?

intra-articular carilage (located at joints where flexion and extension are associated with gliding)

- prevent joint instability

What type of fibrocartilage is found in the TMJ and what is its function?

fibrocartilage (cells are chondrocytes but you can see collagen fiber bundles in the matrix)

What type of tissue is pictured?

Connective tissue on Left (Can see the lines)

Cartilage on right (isolated and round cells, shouldn't see fibers, space is lacunae for condrocytes)

Which side is cartilage and which is CT?

1: Cartilage, articular

Location: joint (absence of perichondrium)

2: Regular dense CT

Ligment, connects two bones

Identify the two tissues. Collagen is stained in blue