What is Isogenous group and how is it formed?
An isogenous group (lat. “equal origin”) is a cluster of chondrocytes, all formed through division of a single progenitor cell, found in hyaline cartilage and elastic cartilage, growing by interstitial growth.
Does fibrocartilage have isogenous groups?
Fibrocartilage appears to be quite different from hyaline cartilage on ultrasound due to the predominance of collagen fibers, which cause increased reflectivity and produce a homogeneously hyperechoic texture. Chondrocytes are scattered singly or in small, isogenous groups in the dense fibrous matrix of the cartilage.
What is hyaline cartilage and where is it located?
Hyaline cartilage is the most widespread and is the type that makes up the embryonic skeleton. It persists in human adults at the ends of bones in free-moving joints as articular cartilage, at the ends of the ribs, and in the nose, larynx, trachea, and bronchi.
What do chondrocytes do?
Chondrocytes in the AC proliferate and secrete extracellular matrix to maintain and sustain the cartilage. The cells themselves are separated from each other by cartilage matrix [2]. They respond to outside stimuli and tissue damage, and are also responsible for degenerative conditions, such as osteoarthritis (OA).
What is the difference between hyaline elastic and fibrocartilage?
Hyaline cartilage contains fibers made primarily of type II collagen only. Fibrocartilage contains type II collagen but also contains abundant type I collagen. Elastic cartilage contains type II collagen and elastic fibers.
Why perichondrium is chondrogenic?
The perichondrium consists of an outer fibrous layer that contains fibroblasts and an inner chondrogenic layer that contains chondroblasts. The main functions of the perichondrium are to protect bones from injury and damage, nourish cartilage through blood vessels, and facilitate cartilage growth.
How fibrocartilage gets its nourishment without perichondrium?
Cartilage is devoid of blood vessels. Thus the nutrition of cells within the cartilage matrix is dependent on the diffusion of nutrients from blood capillaries in the perchondrium and/or adjacent tissues through the matrix. Articular hyaline cartilage and fibrocartilage do not have a perichondrium.
Is fibrocartilage shock absorbing?
Fibrocartilage is considered inflexible and tough. It acts more like a shock absorber. Examples may be found between the vertebrae of the spine and the menisci of the knee.
What happens to hyaline cartilage as we age?
Thinning and yellow discoloration occur in old age. At its margins, articular cartilage merges with a periosteal surface that is lined by fibrous tissue contiguous with the synovial membrane.
What is white collagen?
The main constituent of white fibrous connective tissue is the protein collagen. White fibrous tissue is dense regular connective tissue that has a silvery white colour/appearance and is physically tough, yet pliable.
What is the function of Chondroblast?
Chondroblasts, located in the perichondrium, are cells that play an important role in the development of cartilage. By producing extracellular matrix, chondroblasts create the main component that provides structure and strength to cartilage.
What is Fibrocartilaginous?
Fibrocartilage is the tough, very strong tissue found predominantly in the intervertebral disks and at the insertions of ligaments and tendons; it is similar to other fibrous tissues but contains cartilage ground substance and chondrocytes.