Answer
The aging skin changes in the following ways: it becomes thinner and it loses subcutaneous fat. It also becomes drier and rougher because of loss of sebaceous glands .
Aging changes make the skin more susceptible not only to traumatic injury but to to infections--bacterial, fungal, viral, and parasitic (infestations).
This increase in susceptibility to infection is due partly to a decrease in the skin's ability to defend itself immunological. One specific reason for this is that intraepidermal macrophages decrease in number and in efficiency as phagocytes. In addition, the loss of sebaceous glands and the associated increased dryness and brokenness of epidermis leave the skin open to successful attacks by pathogens.
Work Step by Step
In the dermis, blood vessel walls become thicker and less permeable as the skin ages. This impairs nutrient support of the epidermis. Moreover, when epidermal trauma or penetration damages cells of the outer layers of the epidermis , repair is hindered because in the aging skin cells from the basal layer ((stratum germinativum) travel more slowly to the surface.
