how to distinguish the collagen fibers and elastic fibers mi

how to distinguish the collagen fibers and elastic fibers microscopically? What is the major functional difference between these two types of fibers.

Solution

ANS:

Collagen and elastic fibers microscopic observation:

Fibrous components of the extracellular matrix are light-microscopically classified into three types of fibers. They are collagen, reticular and elastic fibers.

A. Collagen fibers:

It looks like cord or tape shaped and present 1-20 microm wide. Collagen fibers are closely packed with thin collagen fibrils (30-100 nm thick). These fibrils can form three-dimensional network by splitting and joining alternatively. In the process of fibrogenesis these are produced by fusing short and thin fibrils with tapered ends. It mainly found in bone, cartilage, tendons and ligaments.

B. Elastic fibers:

Elastic fibers are mainly composed with microfibrils and elastin components. the elastin compounds which are present in elastic fibrers are composed with elastin fibrils about 0.1-0.2 microm thick. These fibers are continuous with bundles of microfibrils and form an elastic network specific to individual tissues. It mainly found in blood vessels and lungs.

Functional difference:

A. Collagen fibers function:

1. provide structural support for the tissues in the human body

2. Flexible but only slightly elastic in nature.

3. It had good tensile strength.

4. It holds body structure together (Ligaments and Tendons)

B. Elastic fibers function:

1. It provide strength and stretching

2. support with flexibility

3. Maintain shape of certain structure of body (External ear).