Chapter 5, part 1
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ight © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Fundamentals of Anatomy & Physiology SIXTH EDITION Chapter 5, part 1 The Tissue Level of Organization-- Integument
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Chapter 5, part 1. The Tissue Level of Organization--Integument. Learning Objectives. List the components of the integumentary system, including their physical relationships. Specify the functions of the integumentary system. - PowerPoint PPT Presentation
Transcript of Chapter 5, part 1
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings
Fundamentals of
Anatomy & PhysiologySIXTH EDITION
Chapter 5, part 1
The Tissue Level of Organization--Integument
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings
Learning Objectives• List the components of the integumentary
system, including their physical relationships.
• Specify the functions of the integumentary system.
• Describe the main features and functions of the epidermis and dermis.
• Discuss individual and racial differences in skin.
• Discuss the effects of UV light on the epidermis.
• Explain the structure and function of the various accessory organs of the skin.
• Explain how the skin responds to injury and aging.
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SECTION 5-1 The Integumentary System: An Overview
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• Cutaneous membrane
• Epidermis
• Dermis
• Accessory structures
• Subcutaneous layer
The integumentary system consists of
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• Protection
• Excretion
• Temperature maintenance
• Nutrient storage
• Vitamin D3 synthesis
• Sensory detection
Integumentary system functions:
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Figure 5.1 The Components of the Integumentary System
Figure 5.1
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SECTION 5-2 The Epidermis
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• The epidermis is composed of layers of keratinocytes
• Thin skin = four layers (strata)
• Thick skin = five layers
Figure 5.2 Thin Skin and Thick Skin
Figure 5.2
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• Provides mechanical protection
• Prevents fluid loss
• Keeps microorganisms from invading the body
The epidermis
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• Stratum germinativum
• Stratum spinosum
• Stratum granulosum
• Stratum lucidum
• Stratum corneum
Layers of the epidermis:
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 5.3
Figure 5.3 The Epidermal Ridges of Thick Skin
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• Cells accumulate keratin and eventually are shed
• Epidermal ridges are interlocked with dermal papillae
• Fingerprints
• Improve gripping ability
• Langerhans cells (immunity) in s. spinosum
• Merkel cells (sensitivity) in s. germinativum
Epidermal characteristics:
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Figure 5.4 The Structure of the Epidermis
Figure 5.4
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• Blood supply
• Carotene and melanin
• Melanocytes produce melanin and protect from UV radiation
• Epidermal pigmentation
• Interrupted blood supply leads to cyanosis
Skin color depends on
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Figure 5.5 Melanocytes
Figure 5.5a, b
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• Synthesize vitamin D3 (cholecalciferol) when exposed to UV
• Respond to epidermal growth factor
• Growth
• Division
• Repair
• Secretion
Epidermal cells
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SECTION 5-3The Dermis
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• Papillary layer
• Contains blood vessels, lymphatics, sensory nerves of epidermis
• Reticular layer
• Contains network of collagen and elastic fibers to resist tension
Dermal Organization
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Figure 5.8 Dermal Circulation
Figure 5.8
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• Caused by excessive stretching of the dermis
• Patterns of collagen and elastic fibers form lines of cleavage
Stretch marks
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Figure 5.7 Lines of Cleavage of the Skin
Figure 5.7
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• Cutaneous plexus arteries found in subcutaneous layer/ papillary dermis
• Cutaneous sensory receptors (light touch, pressure)
Dermal Circulation and innervation
