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pheomelanin - It is yellow to red and is formed by a combination of DOPA and cysteine

eumelanin - typically brown to black and is built from DOPA (dihydroxyphenylalanine)

Scar tissue lacks hair as well as sweat glands!

• Also known as sebaceous glands, these are connected to hair follicles.

• They consist of small sacs with ducts that open into the follicles.

• Sebaceous glands secrete sebum, an oily substance that lubricates the skin and hair, helping to keep them soft and preventing water loss from the skin’s surface.

Sebaceous glands that keep skin moisturized! 💦

Sweat Glands (Sudoriferous Glands):

• Sweat glands are responsible for excreting perspiration (sweat) from the body.

• They help regulate body temperature and eliminate waste products through the skin.

• There are two main types: eccrine glands (found all over the body and important for temperature regulation) and apocrine glands (found mainly in areas like the underarms and groin, associated with scent).

Your skin has two main types of sweat glands:
- Eccrine: All over your body, helping control temperature
- Apocrine: Found in armpits and groin, activated during puberty

https://phys.org/news/2025-02-bitter-receptors-skin-cells-function.html

Its “bricks and mortar” organization-corneocytes as bricks, lipids as mortar-ensures both strength and selective permeability, helping to keep moisture in and harmful substances out!

This layer also contains Langerhans cells, a type of immune cell. These cells are part of the dendritic cell/macrophage family and play a crucial role in antigen presentation and immune surveillance in the skin.

• The papillary layer connects the dermis to the epidermis.

• It contains dermal papillae, which are membranes of ridges and grooves that attach to the epidermis.

• These dermal papillae may contain looped capillaries that nourish the epidermis or tactile corpuscles, which are nerve endings sensitive to touch and pressure.

• The papillary layer comprises about 10–20% of the dermis and has loosely arranged collagen and elastin fibers, making it less dense than the deeper reticular layer.

• The top of the papillary layer, where it meets the epidermis, is called the dermal-epidermal junction

• The reticular layer supplies the skin with all of its oxygen and nutrients through a rich network of blood vessels and lymphatic channels.

• It is composed mainly of dense connective tissue, including collagen and elastin fibers, which provide the skin with strength, structure, and elasticity.

• This layer contains fat cells, blood vessels, sweat (sudoriferous) glands, sebaceous (oil) glands, hair follicles, and arrector pili muscles.

• Damage to the collagen and elastin fibers in the reticular layer is a primary cause of sagging, wrinkles, and loss of skin elasticity as part of intrinsic aging.

• The reticular layer is thicker than the papillary layer and forms the bulk of the dermis, supporting the skin’s overall structure and resilience

This tissue is sometimes referred to as the "fatty tissue" and is critical for both protection and energy storage.

Intercellular: between the cells

Fibroblasts are found in both the papillary dermis (upper layer) and the reticular dermis (lower, thicker layer).

They consist of transmembrane proteins that connect to intracellular structures, specifically the intermediate filament network.

• To understand the complexity of the skin 

• To understand the aging process and factors that affect the skin’s health and appearance 

• To know how to maintain and treat the skin 

Primary focus with skin treatments: preserve, protect, and nourish the skin

Only working on the Epidermis!

Other names for estheticians: technician, skin therapist/specialist