Cartilage

Question 1

What is the composition of cartilage?

Answer 1

Cells called chondrocytes lie in an extracellular matrix
Large quantities of GAGs (particularly hyaluronic acid) and type 2 collagen present create a firm but pliable extracellular matrix which is resistant to pressure whilst still allowing diffusion

Question 2

What are the 3 main types of cartilage?

Answer 2

Hyaline
Elastic
Fibrocartilage

Question 3

Describe hyaline cartilage

Answer 3

Contains only chondrocytes which may form isogenous groups

Matrix contains hyaluronate proteoglycan aggregates bound to type 2 collagen fibres which form a fine matrix

Question 4

Where is hyaline cartilage found?

Answer 4

Articulating surfaces (nose, trachea, rib cage, bronchi and larynx) 
Articulating surfaces of long bones
In embryos as the precursors to most bones

Question 5

Describe elastic cartilage.

Answer 5

Matrix similar to hyaline cartilage except it also contains many elastic fibres and elastic lamellae

Question 6

Where is elastic cartilage found?

Answer 6

Epiglottis
Eustachian tube
External ear (pinna)

Question 7

Describe fibrocartilage

Answer 7

Contains chondrocytes and fibroblasts distributed in rows
Matrix of hyaline cartilage but also contains abundant type 1 collagen
Mixture of dense connective tissue and hyaline cartilage

Question 8

Where is fibrocartilage found and what is its function?

Answer 8

Tempromandibular joint, pubis symphsis, meniscus of knee, intervertebral discs and sternoclavicular joint
Acts as a shock absorber and resists shearing forces