Question

The dermis and the inner layer of the skin provide tensile strength and mechanical support to the muscles, bones, and inner organs. The stratum corneum promotes, not prevents, absorption of topical medications. Fibroblasts, not the basal layer of the epidermis, are responsible for collagen formation. The skin has two layers only: the epidermis and the dermis.

a) Dermis and inner layer
b) Stratum corneum
c) Fibroblasts
d) Basal layer of the epidermis

Answer 1

The skin is composed of the epidermis and dermis. The epidermis includes the stratum corneum, which acts as a barrier, while the dermis contains fibroblasts responsible for collagen formation. Underneath the dermis is the hypodermis, connecting the dermis to underlying tissues.

Step-by-step explanation:

The skin has two main layers which are the epidermis and the dermis. The outermost layer, the stratum corneum, consists of dead cells that help prevent water loss and protect against the invasion of microbes. The stratum corneum does not typically promote absorption of topical medications; rather, it serves as a barrier, although certain chemicals can penetrate this layer.

The epidermis contains cells called keratinocytes, which produce keratin, a protein that gives skin its toughness and water-resistant properties. The basal layer of the epidermis, or stratum basale, is where new skin cells are generated. These cells then move up through the layers of the epidermis to the surface, filling with keratin and eventually dying to form the stratum corneum.

The dermis is the thicker, inner layer beneath the epidermis and is made of connective tissue providing strength and elasticity, thanks to fibers like collagen and elastin. Fibroblasts are the cells within the dermis that are responsible for the formation of collagen and elastin. Beneath the dermis is the hypodermis, which connects the dermis to underlying tissues and contains fat for insulation and protection.