Question

the dermis is made of irregular fibrous connective tissue. what is the structure and makeup of the matrix of this tissue that contributes to the specific functioning of the dermis?

Answer 1

Dermis contains two zones known as papillary and reticular layers. The papillary layer is a thin zone composed of areolar tissue near the dermal papillae. It is rich in small blood vessels and is loosely organized tissue. The loose papillary layer allows the mobility of leukocytes and other defense cells. These cells provide protection against the pathogenic organisms invading through the breaks in the epidermis. The reticular layer of the dermis is deeper and very thick in nature. It contains dense irregular connective tissue.

The reticular layer of the animal skin is composed of leather contributing to the toughness of the tissue. The collagen forms thick bundles in the reticular layers with less ground substance and small clusters of adipocytes. The collagen fibers are irregular and distributed into all directions. The collagen and elastin fibers in dermis function to maintain the shape and also help to prevent severe injuries to underlying structures. The elastin fibers in dermis also help it to recoil back when it is stretched.