Chapter_5_Integumentary_System_edited_with_recordings_1___2___1_

Page 1: Copyright Notice

• All rights reserved by McGraw-Hill Education.

• No reproduction or distribution without permission.

Page 2: Preparation Questions

1. List the 4 tissues that make up the body.

2. Describe exocrine glands.

3. Explain why skin is considered a membrane.

4. Define homeostasis.

5. Define negative feedback.

6. List and describe the components of a feedback loop.

Page 3: The Integumentary System

5.1 Structure of the Skin

• Overview of the skin's structure.

Page 4: Introduction to the Skin

• Skin Types: Cutaneous membrane, largest organ of the body (1.8 m2).

• Comprised of all four tissue types.

• The integumentary system includes skin and accessory organs.

• Regions: Epidermis, dermis, hypodermis/subcutaneous tissue attaches skin to underlying tissue.

Page 5: Skin Anatomy

Key Components

• Epidermis:

• Dermis:

• Hypodermis (subcutaneous layer):

• Includes hair follicles, sensory receptors, and various glands (sebaceous and sweat).

Page 6: Epidermis Overview

• Characteristics: Outer, thinner skin region.

• Structure: Composed of five layers (strata).

• Layers (Deep to Superficial):

  1. Stratum basale

  2. Stratum spinosum

  3. Stratum granulosum

  4. Stratum lucidum

  5. Stratum corneum

Page 7: Skin Layer Structure

• Visual breakdown of epidermis and dermis with respect to skin anatomy.

Page 8: Stratum Basale

• Function: Constant cell division; new cells pushed to the surface.

• Cell Types:

  • Keratinocytes (most numerous, produce keratin)

  • Melanocytes (produce melanin)

  • Albinism: condition with lack of melanin production.

Page 9: Stratum Spinosum and Stratum Granulosum

1. Stratum spinosum: Cells divide, spiny appearance from keratin fibers.

2. Stratum granulosum: Flattened cells, high keratin and pigment granules.

Page 10: Stratum Lucidum and Stratum Corneum

4. Stratum lucidum: Present in thick skin, protects against friction.

5. Stratum Corneum: Tough outer layer, keratinized/dead cells preventing water loss and serving as a barrier against microbes.

Page 11: Dermis

• Composition: Dense irregular connective tissue, collagen and elastic fibers.

• Dermal features: Includes dermal papillae, vascularization (supplies nutrients and oxygen), and numerous sensory nerve fibers.

Page 12: Skin Anatomy Reiteration

• Provides a detailed view of skin structures and layers, highlighting various components such as hair follicles, glands, and nerve fibers.

Page 13: Hypodermis

• Description: Located below the dermis, loose connective tissue.

• Function: Energy storage, insulation, padding.

• Subcutaneous injections: Administered here using a hypodermic needle.

Page 14: Accessory Structures of the Skin

5.2 Overview

• Focus on accessory structures associated with the skin.

Page 15: Hair

• Presence: Hair is absent from palms, soles, lips, and certain reproductive organs.

• Development: Noticeable hair in axillary and pelvic regions post-puberty.

Page 16: Hair Structure

• Properties of hair follicles in the dermis formed from epidermal cells.

• Key Components:

  • Hair matrix (cell division & growth center).

  • Hair root vs. Hair shaft.

  • Sebaceous glands and arrector pili muscle: Associated structures.

Page 17: Hair Structure Visual

• Diagram illustrating hair anatomy including the hair shaft, follicle, sebaceous gland, and muscle attachments.

Page 18: Nails

• Formation: Specialized epithelial cells keratinized at nail root.

• Parts:

  • Nail body (visible part)

  • Cuticle (skin fold hiding the root)

  • Lunula: Whitish half-moon shape at nail base.

Page 19: Nail Structure Visual

• Sagittal section of a nail showing various nail components.

Page 20: Exocrine Glands Overview

Function and Types

• Two major types of glands in the skin.

  1. Sweat glands

  2. Sebaceous glands

Page 21: Skin Gland Types Visual

• Diagram of sweat and sebaceous glands showcasing their locations and systems within skin anatomy.

Page 22: Sweat Glands

• Types:

  1. Apocrine glands: Found in specific areas; activated at puberty.

  2. Eccrine sweat glands: Opens onto skin surface; regulates body temperature and excretes waste.

  3. Ceruminous glands: Modified sweat glands (earwax).

Page 23: Sebaceous Glands

• Function: Associated with hair follicles.

• Secretion: Produces sebum; blockage leads to whiteheads/blackheads.

• Acne: Inflammation of sebaceous glands.

• Mammary glands: Modified apocrine glands for milk production.

Page 24: Functions of the Skin

5.3 Overview

• Exploration of skin functions arises.

Page 25: Key Functions of the Skin

1. Protection: Shields against trauma, UV, pathogens.

2. Water regulation: Waterproof barrier.

3. Sweat: Eliminates excess water and waste.

4. Vitamin D production: Prevents Rickets through UV exposure.

5. Sensation: Gathers environmental information.

6. Temperature regulation.

Page 26: Normal vs. Rickets Visual

• Diagrams contrasting normal and Rickets-affected skin.

Page 27: Body Temperature Regulation

• Body heat generated via ATP production.

• Responses to temperature changes:

  • Rise: Mechanisms put in place to cool down.

  • Fall: Alerts systems to create heat.

Page 28: Temperature Regulation Abnormalities

• Hyperthermia: including heat exhaustion and heat stroke.

• Hypothermia: responses and health impacts.

Page 29: Skin Disorders Overview

5.4 Introduction

• Examination of common skin disorders.

Page 30: Common Skin Disorders

• Athlete’s foot: Fungal infection of toes/soles.

• Impetigo: Bacterial infection common in young children.

• Candidiasis: Yeast infection in moist areas.

• Eczema: Inflammation of the skin.

• Dandruff: Produced by dry scalp.

• Urticaria (Hives): Allergic reaction with itchy patches.

Page 31: Skin Cancer Basics

• Skin cancer begins with DNA mutation.

• Types:

  • Nonmelanoma: including basal and squamous cell carcinoma.

  • Melanoma: a more dangerous form.

Page 32: ABCDES of Skin Cancer Detection

• ABCDE Rule for Melanoma:

  • Asymmetry

  • Border irregularities

  • Color variances

  • Diameter greater than 6 mm

  • Evolving characteristics.

Page 33: Basal Cell Carcinoma

• Description: Most common skin cancer.

• Caused by UV radiation affecting basal cells.

• Variability in signs; high chance of successful treatment.

Page 34: Basal Cell Carcinoma Visual

• Diagrams depicting signs of basal cell carcinoma.

Page 35: Squamous Cell Carcinoma

• Description: Less common, but more likely to spread and fatal in some cases.

• Signs resemble basal cell carcinoma with possible warty/scaly growths.

Page 36: Squamous Cell Carcinoma Visual

• Illustrative examples of squamous cell carcinoma.

Page 37: Melanoma Characteristics

• More aggressive form of skin cancer.

• Originates in melanocytes; associated with sunburn severity.

• Rising incidence over the past decade.

Page 38: Melanoma Visual

• Images showcasing melanoma presentation.

Page 39: Prevention Strategies

• Methods:

  • Use broad-spectrum sunscreen (SPF 15+).

  • Wear protective clothing.

  • Utilize UV-protective sunglasses.

  • Avoid sun exposure during peak hours.

  • Steer clear of tanning beds.

Page 40: Notes on Moles and Warts

• Kaposi's sarcoma: Opportunistic in immunocompromised individuals.

• Moles (melanocyte growths) and warts (virus-induced) are not typically cancerous.

Page 41: Wound Healing Process

• Inflammatory Response: Symptoms include redness, swelling, heat, pain.

• Steps:

  1. Blood fills the wound; clot formation.

  2. White blood cells and fibroblasts migrate.

  3. Fibroblasts promote tissue regeneration and close wound margins.

  4. New cells produced by the basal layer of epidermis.

  5. Fibroblasts generate scar tissue.

Page 42: Wound Healing Visual

• Diagram outlining steps and healing progress through various phases of wound healing.

Page 43: Burn Types Overview

• Burns can stem from heat, chemicals, radiation, or electrical sources.

• Severity assesses based on depth and area affected.

Page 44: Types of Burns

1. First-degree: Partial-thickness burn.

2. Second-degree: Partial-thickness burn.

Page 45: Advanced Burn Types

3. Third-degree: Full-thickness burns.

4. Fourth-degree: Involves deeper tissues down to the bone.

Page 46: Rule of Nines for Burns

• Technique to estimate the extent of burns on the body.

• Lund-Browder chart: Specifically adapted for children.

Page 47: Rule of Nines Visual

• Illustrative representation of the "Rule of Nines" for burn assessment.

Page 48: Critical Burn Conditions

• Conditions under which burns are considered critical:

  • Second-degree burns covering >25% body.

  • Third-degree burns covering >10% body.

  • Any fourth-degree burn area.

  • Third-degree burns on face, hands, or feet.

Page 49: Effects of Aging Overview

5.5 Aging Impact

• Discussion of aging's effects on the integumentary system.

Page 50: Aging Effects on Skin

1. Reduced mitosis rates of skin cells.

2. Thinning dermis and flattening dermal papillae.

3. Decrease of adipose tissue in hypodermis.

4. Loss of collagen.

5. Wrinkles from decreased padding, fiber loss, and UV exposure.

Page 51: Additional Aging Effects

6. Limited adjustment to heat due to fewer blood vessels and sweat glands.

7. Decreased hair follicle numbers.

8. Reduced sebaceous gland count.

9. Melanocyte reduction.

10. Accumulated sun damage effects.

Page 52: Homeostasis Overview

5.6 Skin and Homeostasis

• Role of skin in various organ systems.

Page 53: Skin's Role in Homeostasis

• Interacts with lymphatic system for protection.

• Aids kidneys in water balance and waste excretion.

• Stores calcium in skeletal system.

• Senses environmental changes through the nervous system.

Page 54: Continued Interactions in Homeostasis

• Supports muscular system in temperature maintenance.

• Interdependent with cardiovascular, respiratory, digestive, renal systems.

• Responds to endocrine hormones and aids reproduction.