Your Skin Part II

1
Your Skin Part II

• The Dermisthe true, living skin!

2
The Dermis

• The dermis is a tough supportive connective
  tissue matrix containing numerous specialized
  structures.
• The dermal thickness varies
• thinnest (0.6 mm) on the eyelids
• thickest (3 mm or more) on the back, palms, and
  soles.

3
The Dermis (Continued)

• Collagen fibers
• 70 of the dermis
• structural toughness and strength.
• Elastic fibers
• loosely arranged in all directions
• elasticity to the skin.
• most prevalent
• hair follicles
• sweat glands

4
Specialized Cells of the Dermis

• fibroblasts
• synthesize collagen, elastin, other connective
  tissue
• dermal dendrocytes
• dendritic cells with immune function
• ??? NAME THIS CELL ???
• mast cells, macrophages, and lymphocytes.
• All involved in immune response

5
Specialized Structures in the Dermis

• Hair Follicles
• Sebaceous Glands
• Sebum Secreation
• Melanocytes
• Located bi-laterally to base of hair bulb
• Concentration varies in individuals
• Interaction of your keratin and your melanin
  your hairs color

6
Specialized Structures in the Dermis (continued)

• Sweat Glands
• AKA Apocrine Glands
• Secretory portion (pseudostrtified cuboidal)
• Water transferred to epidermal surface
• Position of duct in relation to hair fiber
• Function of erector pilli m.????
• Why does sweating cool you?
• Absorptive (Duct) Portion (Stratified cuboidal)
• What and where from?

7
Sweat Glands of the Dermis

• Secretory portion
• pseudostrtified cuboidal epithelium
• Cytoplasm appears light pink
• Absorptive (Duct) Portion
• Stratified cuboidal epithelium
• Cytoplasm appears dark pink

8
Mast Cells

• Antigen Binders
• 1st wave of Complement
• Any needed molecules for winning the battle
• Ex. Histamines vs. pollen

9
Macrophages

• Phagocytic Cells
• Abundant Endosomes
• Modified vacuoles
• Hold strong, digestive enzymes
• Breakdown pathogens and undesirables

10
Macrophages (Continued)
11
Layers of the Dermis

• Papillary dermis
• the thin upper layer
• lies directly below and interdigitates with the
  epidermal rete ridges
• papillary dermis is composed of loosely
  interwoven collagen.

12
Layers of the Dermis

• Reticular dermis
• Deep to and thicker than the Papillary Dermis
• Collagen arraignment
•   coarse, horizontally running bundles of
  collagen.

13
Layers of the Dermis

• Subcutaneous Layers
• Mostly adipose connective tissue
• Function
• Binds the dermis to underlying organs