CBSE Class 9 Answered
Bone is an example of connective tissue. It is porous, hard and highly vascular.
The bone cells called osteocytes are embedded in a hard matrix. This matrix is made up of calcium, magnesium and phosphorous compounds. The matrix of bone shows lamellae, which are thin, concentric rings. Bone cells called osteocytes, are present in lacunae (fluid filled spaces between the lamellae). All lacunae communicate with each other by network of fine canals called canaliculi. Each canaliculus contains slender process of the bone cell. The central haversian canal contains blood vessels and nerve fibres.
Cartilage is less vascular. The cells of cartilage are widely spaced and called chondrocytes. The matrix is extensive and is composed of proteins, sugars and salts.
Matrix is firm but also slightly elastic. Hence, regions containing cartilage is flexible. Matrix is produced by chondrocytes. Chondrocytes are also present in lacunae.