The Integumentary System

1
The Integumentary System

• February 22, 2006
• BIOL 203
• Karen Kraus

2
Triple Layer

• Epidermis
• Dermis
• Hypodermis

3
Above it all

• Stratified squamous (keratinized)
• Four or five layers of ever-flatter keratinocytes
• also includes melanocytes, Langerhans cells and
  Merkel cells

4
The Worlds Palette

• Melanin is produced using phenylalanine and/or
  tyrosine
• eumelanin is brown or black
• phaeomelanin is yellow or red
• Other skin colors are due to other pigments
• carotene
• hemoglobin
• Skin color can be indicative of DISEASE

5
Layer it on.

• Stratum Basale
• Stratum Spinosum
• Stratum Granulosum
• Stratum Lucidum
• Stratum Corneum

6
Middle child

• Connective tissues
• dense irregular
• areolar
• Two indistinct layers
• Vascular
• Variety of structures and cells

7
Heavy Metal Papillon

• Superficial layer
• dermal papillae meet epidermal pegs
• sensory receptors
• thermoregulation via radiation

8
Reticular in name only

• Does not include reticular tissue!
• Collagen binds water
• Pacinian corpuscles
• Sweat glands
• Deep parts of hair follicles
• Strength and elasticity of the skin

9
Can you hear me now?

• Cutaneous reception
• encapsulated or unencapsulated
• no capsules
• free nerve endings (pain, stretch, temp)
• root hair plexus (movement)
• capsules
• touch receptors

10
Feel it!

• Meissners corpuscle (light)
• Pacinian corpuscle (deep)
• Ruffinis corpuscle (deep)
• Krauses end bulb (light)

11
The beast within

• Vestigial remnants
• dead keratinocytes
• follicle -- internal and external root sheath
• matrix cells
• arrector pili
• sebaceous gland
• holocrine

12
More beast

• free edge, body, root
• matrix
• nail bed
• lunula
• cuticle

13
Sweat it, baby!

• Eccrine
• merocrine
• pore
• thermoregulatory
• Apocrine
• merocrine
• hair shaft
• possibly pheromone release