Cartilage

Question 1

How are metabolic processes maintained in cartilage?

Answer 1

Avascular so nutrition comes from simple diffusion from passing blood vessels

Question 2

Name the 3 types of cartilage

Answer 2

1. Hyaline
2. Elastic
3. Fibro-cartilage

Question 3

What are the features of hyaline cartilage?

Answer 3

• abundant ground substance
• some Type 2 collagen fibres
• glossy appearance
• forms temporary skeleton in embryo
• responsible for growth of long bones
• found mainly on articular surfaces of joints in adults

Question 4

What are the features of elastic cartilage?

Answer 4

• flexible
• contains elastic fibres and Type 2 collagen
• found in ear pinna and epiglottis
• consists of perichondrium, chondroblasts, chondrocytes and lacunae

Question 5

What are the features of fibro-cartilage?

Answer 5

• intermediate between dense regular CT and hyaline cartilage
• large collagen Type 1 fibres
• function is stress/weight bearing
• limited distribution - intervertebral discs, intra-articular discs, attachment of ligament to bone
• chondrocytes arranged in columns between bundles of collagen
• minimal ground substance
• interstitial growth

Question 6

What are the 2 ways by which cartilage can grow?

Answer 6

1. Interstitial growth - occurs from within the cartilage. Chondroblasts form isogenous groups which deposit more cartilage
2. Appositional growth - formation and deposition onto a surface/edge of pre-existing cartilage on the perichondrium. Chondroblasts arise from fibroblasts in surrounding general CT and produce cartialge ECM