3 Membranes and the Integumentary System Lesson 3.1: Body Membranes Lesson 3.2: The Integumentary System Lesson 3.3: Injuries and Disorders of the Skin

Chapter 3: Membranes and the Integumentary System Lesson 3.1 Body Membranes

Do Now – Pick 4 words and write the definition of each. Membranes – Pg. 84 Pleura – Pg. 84 Cutaneous Membranes – Pg. 84 Serous Fluids – Pg. 84 Serous Membranes – Pg. 84 Epithelial Membranes – Pg. 84 Synovial Fluid – Pg. 84 Mucous Membranes – Pg. 84 Synovial Membranes – Pg. 84 Pericardium – Pg. 84 Peritoneum – Pg. 84

Today’s Objectives Identify the different types of body membranes and explain their functions. Explain the purposes of serous fluid and synovial fluid.

Body Membranes Membranes – surround and help protect the body’s surfaces. Include cavities that open to the outside world, internal cavities that house body organs, capsules that surround ball-and-socket synovial joints and the skin. Epithelial membranes mucous membranes serous membranes cutaneous membranes connective tissue membranes synovial membranes

Epithelial Membranes Mucous membranes line cavities open to the environment Includes all of the hollow organs of the respiratory, digestive, urinary, and reproductive tracts. Examples: mouth, nose, lungs, digestive tract, and bladder. Structure Comprised of a layer of epithelium on top of loose connective tissue Mucous membranes are all moist: the membranes of the digestive and respiratory tracts secrete mucus, and glands in the urinary tract add mucus there. Mucus is a slippery solution that protects the mucous membranes and aids in transporting substances.

Serous membranes line cavities not open to environment Structure pleura – encloses the lungs Pericardium – surrounds the heart Peritoneum – lines the abdominal cavity Structure Outer layer of simple squamous (flattened) epithelium on a thin layer of loose connective tissue. Secrete a thin, clear fluid called serous fluid Lubricates between the parietal and visceral membranes to minimize friction and “wear and tear” on organs that move within the linings, such as the heart.

Cutaneous membranes form what we know as skin Structure The basic structure of skin is a keratinizing stratified (layered) squamous epithelium over dense, fibrous connective tissue.

Mucous Membranes and Serous Membranes

Connective Tissue Membranes Synovial membrane capsule around synovial joint Example: Shoulder and knee tendon sheath – the connective tissue that surrounds tendons, as well as bursae Bursae – the small connective tissue sacs that serve as cushions for tendons and ligaments surround the joints. synovial fluid – provides cushioning and reduces friction and wear on moving structures.

Review and Assessment Match these words with 1–4 below: synovial, mucous, cutaneous, serous. 1. line cavities open to the environment 2. line cavities not open to the environment 3. tendon sheath 4. form skin

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Exit Ticket Membranes surround and protect which of the following surfaces? a. ball-and-socket synovial joints b. internal cavities housing organs c. cavities open to the outside world d. all of the above e. none of the above

2) True or False: Mucous Membranes tend to be dry 2) True or False: Mucous Membranes tend to be dry. 3) ______ membranes provide a lining for the internal and external surfaces of the body. a. Mucous b. Cutaneous c. Serous d. Epithelial

4) The cutaneous membrane is the same name for what we know as ____________. a. the lungs b. the digestive tract c. the skin d. the bladder

5) True or False: Serous fluid serves as a lubricant between membranes to minimize friction.

Answers D. All of the above False D. Epithelial C. The Skin True

The Integumentary System Chapter 3: Membranes and the Integumentary System Lesson 3.2 The Integumentary System

Do Now – Pick 4 words and write the definition of each. Integumentary System – Pg. 91 Epidermal dendritic Cells – Pg. 91 Keratin – Pg. 91 Merkel Cells – Pg. 91 Melanocytes – Pg. 91 Papillary Layer – Pg. 91 Melanin – Pg. 91 Reticular Layer – Pg. 91 Epidermis – Pg. 91 Sudoriferous Glands – Pg. 91 Dermis – Pg. 91 Sebaceous Glands – Pg. 91 Hypodermis – Pg. 91 Sebum – Pg. 91 Keratinocytes – Pg. 91

Today’s Objectives Explain how the skin continually regenerates. Describe the processes by which the skin helps to regulate body temperature. Explain the different protective functions of the skin. Identify the different glands and sensory receptors present in skin and describe their functions.

The Integumentary System Functions of the integumentary system Anatomy of the skin Appendages of the skin

Functions of the Integumentary System The skin forms a protective cover that serves a variety of purposes. The skin acts as the first line of defense in protecting the underlying tissues. protects against abrasion chemical damage drying out UV radiation damage

regulates body temperature When the body is overheated, capillaries dilate (expand), allowing heat to escape. Sweat glands become active by producing sweat that evaporates which cools the skin. During cold temperatures, the capillaries constrict (tighten), and blood flow moves to deeper vessels away from the skin to minimize heat loss.

The skin contains specialized cells in the skin called melanocytes. Melanocytes produce melanin. Melanin is the pigment that protects the body against the harmful effects of the sun. Melanin is responsible for human skin color. The skin also contains specialized cutaneous sensory receptors. These receptors transmit nerve signals that contain information about the environment, including touch, pressure, vibration, pain, and temperature.

The skin contains keratin - the skin’s outermost layer Keratin is a tough protein also found in hair and nails that adds structural strength. Helps protect the skin against damage from harmful chemicals. Serves as a water barrier and prevents water from entering the body during bathing or swimming.

Functions of the Integumentary System

Anatomy of the Skin epidermis dermis hypodermis

Review and Assessment True or False? 1. The dermis is the superficial layer of the skin. 2. The skin helps regulate body temperature. 3. The epidermis has three layers. 4. The hypodermis is above the dermis. 5. The skin protects against UV radiation.

Epidermal Cells The epidermis is the outer layer of the skin. This is the layer of skin that we see. Contains 5 layers of tissue from superficial to deep. Starting from the outside and going deep Stratum corneum – consists of dead cells that continually shed. Stratum lucidum – thick skin found on palms, fingers, soles of the feet, and toes. Stratum granulosum - Stratum spinosum Stratum basale – absorbs nutrients from the adjacent dermis. Produce new skin cells.

Layers of the Epidermis

Epidermis keratinocytes epidermal dendritic cells Merkel cells produce keratin, form layers of epidermis epidermal dendritic cells Respond to foreign bacteria or viruses to ward off infections Merkel cells Located in the stratum basale Function: touch receptors Relay touch information to the brain.

Dermis dense, fibrous connective tissue composed of collagen and elastic fibers. Collagen provides toughness and binds with water to keep inner skin moist. Elastic fibers keep the skin from wrinkling or sagging. Phagocytes in the dermis are responsible for ingesting foreign material including bacteria and dead cells.

Dermis papillary layer reticular layer forms fingerprints Includes blood, sweat, oil glands, involuntary muscle, hair follicles and nerve endings

Hypodermis Made up of fibrous connective tissue adipose tissue provides: padding insulation energy storage

Appendages of the Skin sudoriferous (sweat) glands sebaceous glands Eccrine – major sweat glands of the body secretes primarily water. Apocrine – located in the genital and armpit areas. sebaceous glands Located all over the body Produce oily substance called sebum hair nails

Review and Assessment Fill in the blanks with: hypodermis, keratinocytes, sweat, or papillary. 1. Eccrine is a type of _______________ gland. 2. _______________ produce keratin. 3. Adipose tissue is found in the _______________. 4. The _______________ of the dermis forms fingerprints.

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Exit Ticket The skin is made up of which two layers? a. epidermis and hypodermis b. epidermis and dermis c. hypodermis and dermis d. dermis and underlying tissue

2) Which of the following are considered to be appendages of the skin 2) Which of the following are considered to be appendages of the skin? a. Sweat glands b. Hypoglands c. Hair d. Both A and C e. All of the above

3) True or False: Keratin is primarily responsible for human skin color.

Injuries and Disorders of the Skin Chapter 3: Membranes and the Integumentary System Lesson 3.3 Injuries and Disorders of the Skin

Injuries and Disorders of the Skin injuries of the skin infections of the skin and membranes inflammatory conditions of the skin and membranes cancers of the skin

Injuries of the Skin decubitus ulcers burns bedsores caused by restricted blood supply burns first-, second- or third-degree caused by heat, chemicals, electricity or UV radiation rule of nines Suzanne Tucker/Shutterstock.com, JTeffects/Shutterstock.com, Naiyyer/Shutterstock.com

Infections of the Skin and Membranes viral infections herpes varicella herpes zoster herpes simplex virus type 1 or type 2 human papillomavirus warts Maksym Bondarchuk/Shutterstock.com

Infections of the Skin and Membranes fungal infections athlete’s foot jock itch ringworm toenail fungus bacterial infections impetigo cellulitis

Inflammatory Conditions of the Skin and Membranes pleurisy makes smooth surface of pleura rough peritonitis infection of peritoneum psoriasis involves redness and irritation Kenxro/Shutterstock.com

Cancers of the Skin basal cell carcinoma squamous cell carcinoma malignant melanoma ABCD rule Librakv/Shutterstock.com

Review and Assessment True or False? 1. Herpes zoster causes decubitus ulcers. 2. Peritonitis is an infection of the skin. 3. Impetigo is caused by a fungus. 4. Warts are caused by a virus. 5. Ringworm is caused by a fungus.