Study Guide - Chapter 5 PDF

**[Study Guide - Chapter 5]** *This guide is meant to be used in conjunction with your notes in order to learn the material from Chapter 5. It is more of an outline and is not meant to be all-inclusive.* **Introduction** - Integumentary System 1. Cutaneous Membrane a. Epidermis b....

**[Study Guide - Chapter 5]** *This guide is meant to be used in conjunction with your notes in order to learn the material from Chapter 5. It is more of an outline and is not meant to be all-inclusive.* **Introduction** - Integumentary System 1. Cutaneous Membrane a. Epidermis b. Dermis 2. Accessory Structures c. Hair d. Nails e. Multicellular Exocrine Glands - Sweat glands - Oil glands - Hypodermis (subcutaneous layer) - not part of the skin, it is superficial fascia - You should be able to list the many [functions] of skin. **5-1 -- The Structure and Function of the Epidermis** - Where is each type of skin found? - How many layers (strata) are in each type? 1. **Stratum basale** - Contains **basal cells**, **tactile cells**, and **melanocytes** - **Epidermal ridges** \> fingerprints 2. **Stratum spinosum** - 8-10 layers of keratinocytes - **Dendritic** (Langerhans) **cells** -- immune function 3. **Stratum granulosum** - 3-5 layers of keratinocytes - Cells are dehydrating and dying as they become keratinized i. **Keratin** ii. **Keratohyaline** 4. **Stratum lucidum** (only found in thick skin) - 3-5 layers of dead keratinocytes 5. **Stratum corneum** - In thick skin, 15-30 layers of dead, dehydrated keratinocytes that remain tightly bound to one another (due to desmosomes) even though they are dead - Water resistant - Constantly being shed at the apical surface **5-2 -- The Structure and Function of the Dermis** 1. **Papillary Layer** - Composed of areolar connective tissue - Contain small blood vessels, lymphatics, and nerve endings - Blood supply is the **subpapillary plexus** - Forms structures called **dermal papillae** - Interdigitate with the epidermal ridges - In thick skin, may contain fine touch receptors **Tactile** (Meissner's) **corpuscles** - Becomes inflamed during **dermatitis** 2. **Reticular Layer** - Composed of dense irregular connective tissue - Contains larger blood vessels, lymphatics, and nerve endings - Blood supply is the **cutaneous plexus** - Contains pressure receptors called **Lamellar** (Pacinian) **corpuscles** **5-3 -- The Structure and Function of the Subcutaneous Layer** **5-4 -- Skin Color** A. Skin pigments A. **Melanin** - Brown pigment produced by **melanocytes** - Stored in **melanosomes** and transferred to keratinocytes - Differences in skin color are dependent on the amount of melanin produced, not the number of melanocytes - Protects the basal (germinative) cells in the stratum basale from UV damage, which can lead to skin cancer - Be familiar with the ABCDEs of identifying melanoma in the early stages A. **Carotene** - Orange/yellow pigment from vegetables that can accumulate in the dermis B. Blood circulation - When the blood flow to the skin increases - Blood that is well oxygenated lends a reddish hue to the skin - When blood flow decreases or when the blood lacks proper oxygenation - This may lend a blueish hue to the skin (**cyanosis**) **5-5 -- Sunlight and Vitamin D Production** **5-6 -- Hair** 1. **Hair follicle** - What is its purpose - How does it form? - What type of sensory receptor is associated with it and what does it do? - **Root hair plexus** (also called a **hair follicle receptor**) 2. **Hair** - **Hair root** - Base is the **hair bulb** - **Hair shaft** 1. **Arrector pili muscles** -- smooth muscle that causes goose bumps 2. **Sebaceous glands** -- secrete oil into a hair follicle **5-7 -- Exocrine Glands of the Skin** 1. **Sebaceous Glands** (oil glands) - What is the structure of a sebaceous gland? - What is the product it secretes? - **Sebum** (oil) - What is it made of and what is its purpose? - What mode of secretion produces sebum? **Holocrine** - How does sebum get from the sebaceous gland to the surface of the skin? - What is a **sebaceous follicle**? How does the sebum get to the surface of the skin? 2. **Sudoriferous Glands** (sweat glands) A. **Apocrine sweat glands** - Where are they found? - What mode of secretion? - How does the secretion get to the surface of the skin? - What are the qualities of this type of sweat? B. **Merocrine (Eccrine) sweat glands** - What is the structure of the gland? - How does the secretion get to the surface of the skin? - What mode of secretion? - What is the basic composition of the secretion? - What is the purpose of this type of secretion? - What is **sensible perspiration** vs. **insensible perspiration**? 3. **Mammary Glands** - milk glands produce milk in the female breast to nourish an infant 4. **Ceruminous Glands** -- glands in the ear canal produce ear wax for protection of the eardrum **5-8 -- Nails** A. **Nail** a. **Nail root** (area of growth) b. **Nail body** c. **Free edge** - Skin beneath the free edge is called the **hyponychium** B. Associated structures d. Skin folds - **1 Proximal nail fold** - **Eponychium** (cuticle) extends from this skin fold - **2 Lateral nail folds** e. **Nail bed** -- underneath the nail - **Lunula** -- crescent shaped pale part **5-9 -- Skin Response to Injury** - Scab - Granulation tissue - Scar - Keloid **5-10 -- Effects of Aging on the Skin**