Structure and Functions of Cartilage Tissue
The Structure (Physical Description)
of cartilage tissue in general
Cartilage is a connective tissue consisting of a dense
matrix of collagen fibres and elastic fibres embedded in a rubbery
ground substance. The matrix is produced by cells called chondroblasts,
which become embedded in the matrix as chondrocytes.
That is, mature cartilage cells are called chondrocytes.
They occur, either singly or in groups, within spaces called lacunae (sing. lacuna)
in the matrix.
The surface of most of the cartilage in the body is surrounded
by a membrane of dense irregular connective tissue called perichondrium.
This is important to remember especially because
(unlike other connective tissues), cartilage contains no blood
vessels or nerves - except
in the perichondrium.
There are three different types (structures) of cartilage
that have slightly different structures and functions.
They are hyaline cartilage,
and elastic cartilage,
described separately in the sections below:
1.0 Where in the body is hyaline cartilage tissue ?
Hyaline cartilage is the most abundant of the three types of
It is found in many locations in the body,
- Bronchi; Bronchial Tubes; Costal
Cartilages; Larynx (voice-box); Nose; Trachea
- Covering the surface of bones at joints - especially in areas
where damage due to wear may lead to osteoarthritis incl.
of the long bones, and also the anterior
ends of the ribs.
- Embryonic skeleton (i.e. in the fetus).
2.0 The Structure of hyaline cartilage
Hyaline cartilage consists of a bluish-white, shiny ground
elastic material with a matrix of chondroitin sulphate
into which many fine collagen fibrils are embedded.
It contains numerous chondrocytes.
3.0 The Functions of hyaline cartilage tissue
Hyaline cartilage tissue provides smooth surfaces,
enabling tissues to move/slide easily over each other, e.g.
smooth movements at joints. It is also provides flexibility
1.0 Where in the body is fibrocartilage tissue ?
- Calli (sing. callus),
which is the tissue formed between the ends of the bone at
the site of a healing fracture
(blood clot -> granulation tissue -> cartilage -> bone);
discs (i.e. the discs between the vertebrae
of the spine);
- Menisci (cartilage pads) of the knee joint.
- Pubic symphysis, which is the position at which the hip bones
join at the front of the body.
- Also in the portions of the tendons that
insert into the cartilage tissue, especially at joints.
2.0 The Structure of fibrocartilage
Fibrocartilage is a tough form of cartilage that consists of
chondrocytes scattered among clearly visible dense
bundles of collagen fibres within the matrix. Fibrocartilage
lacks a perichondrium.
3.0 The Functions of fibrocartilage tissue
Fibrocartilage tissue provides support and rigidity to
attached/surrounding structures and is the strongest of
the three types of cartilage.
1.0 Where in the body is elastic cartilage tissue ?
- Auditory (Eustachian) Tubes;
- External Ear (Auricle);
- Epiglottis (the lid on the top of the larynx).
2.0 The Structure of elastic cartilage
In elastic cartilage, which is yellowish in colour, the cartilage
cells (chondrocytes) are located in a threadlike
network of elastic fibres within the matrix of the
cartilage. A perichondrium is present.
3.0 The Functions of elastic cartilage tissue
Elastic cartilages provides support to surrounding structures
and helps the define and maintain the shape of the area in
which it is present, e.g. the external ear.
See also the related page about the
structure and functions of bone tissue.