Cartlige

Question 1

classification of skeletal connective tissue

Answer 1

1. Bone
2. Cartilage:

Hyaline- ventral end of ribs

Fibrocartilage- intervertebral discs

Elastic - outer ear

Articulator hyaline cartilage- joints shock absorbers bathed in synovial fluid

Question 2

Cartilage

Answer 2

Specialised type of connective-tissue

Relatively a vascular penetrated by vascular channels from surrounding tissues perichondral blood vessels

No nerve or blood supply

During early embryonic life skeleton is mostly cartilage which is gradually replaced by bone ossification

Flexible and durable supports but can move

Question 3

Properties of Cartlidge

Answer 3

Stiff load-bearing tissue

High resistance to tensile compression and sheering forces

Both resilience and elasticity which allows It to return to its original shape after deformation

Question 4

Component of cartilage

Cells

Answer 4

1. Cells

Chondroplasts:
immature cells — Produce extracellular matrix

Chondrocytes:
Mature cells — maintain extracellular matrix

Cells either singularly or in groups occupying small spaces called lacunae in the matrix which conform to the cell shape

Question 5

Components of cartilage

Extracellular matrix fibres and ground substance

Answer 5

1.Ex.M Fibres

Meshwork of collagen mainly strong Type II fibres are embedded within the ground substance

The meshwork arrangement of the collagen gives strength and also helps to hold the gel like substance in place

2.Ground substance

Frim gel

60–90% water lipids electrolytes and complex macro molecular protein called proteoglycan

Ground substance allows diffusion of nutrients

Question 6

What happens when loading articular cartilage

Answer 6

On loading – Fluid pressure rises immediately cartilage gradually deforms water moves out of cartilage

Afterloading – fluid pressure dropped and cartilage gradually returned to its normal shape water moves back into cartilage

Question 7

Collagen arcade

Answer 7

Describes arrangement of fibres helps collagen to take stresses and strains and be durable and flexible

Chondrocytes aunt closely packed together

Cartilage lays on top of bone

Question 8

Nutrition Of cartilage

Answer 8

Relatively a vascular tissue main source of nutrition is perichondral blood vessels

Sources of nutrition: Receives its nutrition by diffusion from:

1. underlying cancellous bone
2. The synovial membrane at the periphery of the cartilage
3. the synovial fluid in the joint

Poor at repairing due to poor blood supply

Question 9

Perichondrium

Answer 9

A layer of dense connective tissue that surrounds the perimeter of most Cartlidge services

Articular cartilage is not covered by Perry Cardium

Composed of: 2layers

Outer layer- Consists of fibroblasts which produce collagen

Inner layer: contains an differentiated cells I stem cells which can develop into chondroplasts important in growth and repair

When cartilage turns into bone perichondrium turns into periosteum

Question 10

Proteoglycan

Answer 10

Found within ground substance

Complex macromolecules
Core to protein attatched to glycosaminoglycans

Proteoglycans = molecular sponge allows compressibility and shock absorber

Proteoglycan and water are held in position by the mesh work of collagen fibres and allows cartilage to be compressible

Question 10

Healing and repair

Answer 10

Low ability to regenerate

In adults damage to cartilage results infibrous scar tissue

Question 11

Summary histology

Answer 11

Chondrocytes maintain fine balance of decoration and repair

Collagen – forms a Web of arches which constrain the proteoglycans gel

Combination of proteoglycans and collagens act as a molecular sieve;

Admit small particles
Excludes larger particles

Question 12

What are the components of cartilage

Answer 12

1. Extracellular matrix fibres
2. Extracellular matrix
3. Ground substance