Epidermal Ridges: the ridges of the epidermis found in the palms and soles, where the sweat pores open; form in fetus as epidermis conforms to the dermal papillae aka fingerprints
Dermal Papillae: finger like projections in the papillary region of the dermis where the epidermis conforms for fingerprints
dermal papillae that create epidermal ridges
Dermal papillae
Epidermal Ridges
fingerprints
Dermal Papillae
Dermis
In the human skin, the dermal papillae (DP) (singular papilla, diminutive of Latin papula, 'pimple') are small, nipple-like extensions (or interdigitations) of the dermis into the epidermis. They can be observed at the surface of the skin in hands and feet as [[Epidermal ridge|epidermal]] or [[Papillary ridge|papillary ridges]] (colloquially known as fingerprints. The dermal papillae nourishes all hair follicles and bring food and oxygen to the lower layers of epidermal cells. The pattern of ridges they produce in hands and feet are inherited features that are developed before birth. They remain unaltered (except size) throughout life, and are therefore used for fingerprints. The dermal papillae are part of the uppermost layer of the dermis, the papillary dermis, and the ridges they form greatly increase the surface area between the dermis and epidermis. Because the dermis' main function is to support the epidermis, this greatly increases the exchange of oxygen, nutrients, and waste products between these two layers. Additionally, the increase in surface area prevent the dermal and epidermal layers from separating from each others by strengthening the junction between them. With age, the papillae tend to flatten and sometimes increase in numbers. Dermal papillae also play a pivotal role in hair formation, growth and, cycling.
In the human skin, the dermal papillae (DP) (singular papilla, diminutive of Latin papula, 'pimple') are small, nipple-like extensions (or interdigitations) of the dermis into the epidermis. They can be observed at the surface of the skin in hands and feet as [[Epidermal ridge|epidermal]] or [[Papillary ridge|papillary ridges]] (colloquially known as fingerprints. The dermal papillae nourishes all hair follicles and bring food and oxygen to the lower layers of epidermal cells. The pattern of ridges they produce in hands and feet are inherited features that are developed before birth. They remain unaltered (except size) throughout life, and are therefore used for fingerprints. The dermal papillae are part of the uppermost layer of the dermis, the papillary dermis, and the ridges they form greatly increase the surface area between the dermis and epidermis. Because the dermis' main function is to support the epidermis, this greatly increases the exchange of oxygen, nutrients, and waste products between these two layers. Additionally, the increase in surface area prevent the dermal and epidermal layers from separating from each others by strengthening the junction between them. With age, the papillae tend to flatten and sometimes increase in numbers. Dermal papillae also play a pivotal role in hair formation, growth and, cycling.
The dermal papillae are small, nipple-like protrusions of the dermis that reach into the epidermis, bringing food and oxygen to the lower layers of epidermal cells. In addition, a papilla nourishes every hair follicle. Rows of papillae protruding from the dermis into the epidermis form ridges that create patterns on the skin of the hands, feet, and body. These papillary ridges on the fingertips are responsible for fingerprints. These ridges develop sometime before birth. Not only is the pattern unique for each individual, but also it never changes except to grow larger.
dermal papillae
Dermal ridges cause the overlying epidermis to form epidermal ridges. Collectively these ridges are called friction ridges.
flexure lines