The layers of the skin and their functions

The skin is the largest organ of the human body and one of the most complex. The skin is made up of many specialized cells and structures that are constantly changing.

The main function of the skin is to act as a barrier against disease-causing pathogens and harsh environments. It also helps regulate body temperature and gather sensory information from the surrounding environment. Additionally, it plays an active role in the body’s immune response to anything it deems harmful.

This article takes a deeper look at the function of the skin and better understands the actual role of each of the three layers of the epidermis, dermis, and subcutaneous tissue.


The epidermis is the outermost layer of the skin. Its thickness depends on its location on the body. It is thinnest on the eyelids (about half a millimeter) and thickest on the palms and soles (1.5mm).

The epidermis consists of five separate layers:

  • Basal layer: This bottom layer, also called the basal cell layer, has columnar cells that push older cells to the surface. As the cells move up, they begin to flatten out and die.This layer is also melanocytes (produces a pigment that gives skin color) and Merkel cells that act as touch receptors.
  • Acanthus: This layer, also called the squamous layer, is the thickest part of the contains newly formed keratinocytes (produces a protein called keratin that makes up hair, skin and nails) and Langerhans cell This helps fight infection.
  • Granular layer: This layer contains more keratinocytes, which are gradually pushed towards the surface of the skin.
  • Translucent layer: This translucent tissue layer is only present on the palms and soles of the feet.
  • Cuticle: This is the top layer of the epidermis that helps the skin retain moisture and prevent harmful substances from entering the body. It’s made of dead, flattened keratinocytes that shed about every two weeks.


The epidermis, the outermost layer of the skin, protects the body from outside influences, keeps the skin hydrated, produces new skin cells, and gives the skin its color.

What is the function of the epidermis?


The dermis is the middle layer of the skin. It contains connective tissue, capillaries, nerve endings and hair follicles.It also contains different glands including sebaceous glands Apocrine glands that produce sebum (a body oil) and sweat.

The leather is divided into two parts:

  • Papillary Dermis: This is the thin upper layer that contains capillaries that help regulate skin temperature and provide nutrients to the epidermis.they also contain Meissner body (transmitting a subtle touch) and lamellar bodies (transmits vibration and pressure sensations).
  • Reticular dermis: This is the thicker lower layer that contains connective tissue and dense bundles of collagen that provide overall elasticity and strength to the skin.

The thickness of the dermis varies depending on its location on the body. On the eyelid, it is about 0.6 mm thick. On the back, palms and soles, the thickness is 3 mm.


The role of the dermis is to support and strengthen the skin, regulate skin temperature, nourish and hydrate the epidermis, and aid in sensation.

What is the function of the dermis?

subcutaneous tissue

The subcutaneous tissue is the innermost layer of the skin. It is mainly composed of fat, connective tissue, larger blood vessels and nerves.

Most of the body fat is stored in the subcutaneous layer. Not only does it keep you safe from temperature changes, it also protects your muscles and internal organs from bumps and falls.

The subcutaneous layer also:

  • store fat cells to store energy
  • Gives the body a smooth, chiseled look
  • Regulates temperature by constriction and dilation of blood vessels
  • as an attachment point for bones, muscles, and other organs to the skin
  • Includes deep pressure sensor
  • Produces a hormone called leptin, which helps keep your body’s metabolism going homeostasis (balance)


The subcutaneous tissue insulates the body and helps regulate body temperature. In addition to storing energy, it protects the body from shocks and connects the skin to muscles, bones and other organs.

What is the role of subcutaneous tissue?


The skin is the largest organ of the human body. It consists of three layers, each with a specific function.

The outermost layer of the epidermis is responsible for producing new skin cells, protecting the body from harmful substances, and retaining moisture to keep the skin well hydrated.

The middle layer of the dermis is responsible for supporting and strengthening the skin. It helps keep the skin moisturized and nourishes the epidermis. It also helps improve sensation and helps regulate skin temperature.

The innermost subcutaneous tissue shields the body from temperature changes and physical shocks. It gives contoured shape to the body and connects the skin with the internal organs. It also stores fat cells for energy and helps regulate body temperature,

Frequently Asked Questions

  • How many layers does the skin have?

    The skin is mainly divided into three layers:

    • Epidermis: outermost layer, containing five sublayers
    • Dermis: middle layer, consisting of two parts papillary dermis (thin, upper layer) and reticular dermis (thick, lower layer)
    • Subcutaneous tissue: the deepest layer of the skin
  • What is the integumentary system?

    The integumentary system is a collection of organs, including skin, hair, nails, endocrine glands, and sensory nerves. The main function of this system is to protect the body from external factors, such as bacteria or pollution.

    understand more:

    Integumentary system: your skin, hair, nails and glands

  • Which skin layers are affected by third-degree burns?

    Third-degree burns affect all layers of the skin: epidermis, dermis, and subcutaneous tissue. These burns may require a skin graft because the damage is so severe that the skin may not repair itself.

  • When getting a tattoo, which layer of the skin is the ink injected into?

    The tattoo needle penetrates the epidermis and injects ink into the dermis, approximately 2 mm below the topmost layer of the skin. A deep infusion of pigment prevents the ink from fraying, making it permanently visible.