{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Biol129_C4 - Integumentary System Integument Means"covering...

Info icon This preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Integumentary System Integument Means “covering” It refers to “skin” and other external structures. • Functions: Protects body from environment Contains body tissues/fluids Assists heat regulation Detects environment, sensation Produces vitamin D
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
2 Skin The one of the largest organs. There are four layers: – Epidermis – Dermis – Subcutaneous tissue (superficial fascia) – Deep fascia Epidermis The outermost layer Composed of keratinized stratified squamous epithelium • Contains Melanocytes to provide color Merkel cells for touch sensation This layer is NOT vascularized, uses diffusion There are 4-5 defined layers of epidermis
Image of page 2
3 Cells of the Epidermis Stem cells – At the base, progenitors of keratinocytes • Keratinocytes – Displaced outward, the produce keratin Langerhan’s Cells (Dendritic Cells) – Immune system, macrophages that fight infection – Found in all epidermis with primary access to environment (oral cavity, esophagus, vagina) Dermis Deeper than epidermis Contains many of the structures in skin Glands, vessels, nerves, sensory organs Has two defined layers: Papillary layer Loose areolar tissue, loosely organized Permits movement of leukocytes Reticular layer Thick layer of dense irregular connective tissue Thick bundles of collagen present If disrupted by stretch, collagen tears resulting in striae or stretch marks
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon