Ans. CARTILAGE
Cartilage is a dense, clear blue-white firm connective tissue (but less strong than bone).
Structure
The cells of cartilage are called chondrocytes. Each chondroycyte lies in a fluid space called lacuna present in the matrix of cartilage. The matrix of cartilage also contains collagen fibers. Blood vessels do not enter cartilage.
Types of Cartilage
There are three type of cartilage:
(I). Hyaline cartilage is strong yet
flexible. It is found covering the ends elf the long bones, in the nose, larynx, trachea and bronchial tubes.
(II).Elastic cartilage is similar in
structure to hyaline cartilage. It
is also quite strong but has marrow
elasticiy due to a network of elastic fibers in addition to
collagen fibers. It is found in
epiglottis, pine etc.
(iii) Fibrous cartilage is very tough and less flexible due to large number of thick collagen fibers present in knitted form. It is found in intervertebral discs.
Spongy bone
Compact bone
BONE
Bone is the hardest connective tissue in body.
Functions
Bones not only help move, support and protect the various parts of body but also produce red and white blood cells and store minerals.
Structure and Types of Bone
The hard outer layer of a bone
is called compact bone while the interior of bone is soft and porous. It is called spongy bone. Spongy bone contains blood vessels and bone marrow. Figure 13.3
Like cartilage, the matrix of bones also Bntains
also Contains
minerals e.g. calcium and phosphate. We know that cartilage contains a single type of cell. On $e other hand, bones contain different types of cell. The mature bone cells are called osteocytes. Figure 13.4