Anatomy Exam 1- Chapter 4: The Integumentary System New

8. List factors influencing skin color?

1. Dermal Blood Supply 2. Thickness of stratum corneum 3. Variable quantities of two pigments: carotene and melanin

5. List and briefly describe four cell types found in the epidermis.

1. Keratinocytes- Produce a tough protein called Keratin. These are the most abundant epithelial cells that form several different layers. 2. Melanocytes- Pigment- producing cells in the epidermis 3. Merkel Cells- Role in detecting sensation 4. Langerhans Cells- Wandering phagocytic cells that are scattered among keratinocytes.

9. List and briefly describe the 2 layers of the dermis. Be sure to include structures associated with each.

1. Papillary Layer (Superficial dermis)- consists of loose connective tissue. Structures associated with this layer include: -Tactile Corpuscles -Dermal Papillae 2. Reticular Layer (Deep Dermis)- Consists of fibers in an interwoven meshwork of dense irregular connective tissue. - Hair follicles -Glands -lamallated corpuscles

2. List 6 functions of the integument.

1. Physical Protection from environmental Hazards 2. Synthesis and Storage of lipid reserves 3. Coordination of immune response to pathogens and cancers in skin 4. Sensory Information 5. Synthesis of vitamin D3 6. Excretion 7. Thermoregulation

14. List 5 functions of hair.

1. Protection from UV light 2. Insulation 3. Guards entrance to nose and ears 4. Movement of the hair sends impulses via nerves to the brain (presence of root hair plexus). Example (Such as when a bug is crawling on your arm) 5. Contraction of the arrector pili muscles This results in goose bumps

13. List and provide locations for the 3 types of hair.

1. Vellus Covers most of the body 2. Intermediate Hairs Covers arms and Legs 3. Terminal Hairs Covers the Head, eyebrows, eyelashes.

1. List 6 general structures that compose the integumentary system

1.Epidermis 2.Dermis: Papillary Layer 3. Dermis: Reticular Layer 4.Hair Follicles 5. Exocrine Glands 6. Nails

7. Define epidermal ridges? Dermal papillae?

Epidermal Ridges are formed by the Stratum basale of the epidermis that extend into the dermis, increasing the area of contact between the two regions. Dermal Papillae are projections from the dermis toward the epidermis. These projections extend between adjacent ridges. Example: Fingerprint- ridge patters on the tips of fingers

3. Skin (cutaneous membrane) is made up of which 2 divisions?

Epidermis and Dermis

20. List 8 changes to the integumentary system that occur with age.

Fewer Active Melanocytes Fewer Active Follicles Reduced Skin Repair Decreased immunity Thin Epidermis Reduced Sweat Gland Activity Thin Dermis Reduced Blood Supply Dry Epidermis Changes in Distribution of fat and Hair

15. List and briefly describe factors that influence hair color.

Hair color is determined due to: -Variation in melanin production by the melanocytes More melanin= darker hair Production of melanin decreases with age. Decreased production= great hair Lack of melanin= white hair

11. Define hypodermis (subcutaneous layer).

Not part of the integument system. Helps stabilize the integument. Also refereed to as superficial fascia.

19. List the function and major components of nails

Provide protection for the tips of the fingers and toes. Free edge, lateral nail fold, lunula, eponychium, hyponychium

17. List 2 major categories of glands and the general function of glands.

Sebaceous Gland and Sweat Gland. Lubricate the epidermis, excrete waste, assists in thermoregulation.

18. Briefly describe and provide location for the following sweat glands: a. Sebaceous glands b. Apocrine glands c. Merocrine glands d. Mammary glands e. Ceruminous glands

Sebaceous Gland: Secret Sebum to lubricate the skin. Found all over the body except for the palms and soles. Apocrine Gland: Produce odorous secretion which contain pheromones. Found: Under the armpit and nipple region. Merocrine Glands: Produce sweat for cooling purposes Found: All over the body, palms and soles. Mammary Glands: Produce milk Found: breasts Ceruminous Gland: Provide protection to ear Found: Ear canal

16. List and briefly describe 4 phases of hair growth.

Stage 1- Active Stage: Hair grows about .33mm per day This lasts for about two to five years Stage 2- Regression The hair follicle begins to undergo regression, and transitions to the resting phase. Stage 3- Resting During the resting phase the hair loses its attachment to the follicle and becomes a club hair ( inactive follicle) Stage 4 Reactivation When follicle reactivation occurs, the club hair is lost and the hair matrix begins producing a replacement hair.

6. List and briefly describe the 5 layers of the epidermis. What is another name for the stratum basale?

Superficial 1. Stratum Corneum- Multiple layers of flattened, dead, interlocking keratinocytes. 2. Stratum Lucidum- Appears as a glassy layer in think skin only. 3. Stratum granulosum- This is the most superficial layer of the epidermis in which all the cells still possess a nucleus. Keratinocytes have begun to produce lots of keratin. 4. Stratum Spinosum- Keratinocytes are bound together by maculae adherens attached to tonofibrils of the cytoskelton. Some Keratinocytes divide in this layer. Langerhan cells and melanocytes are often present. 5. Stratum Basale- Deepest, basal layer. Attachment to basal lamina. Contains epidermal stem cells, melanocytes, and Merkel cells. Another name for the stratum basale is the stratum germinativum.

4. Define "thick" versus "thin" skin. Where can each be found?

Thick skin may be covered by 30 or more layers of keratinized cells. Epidermis in these locations experience all 5 layers and may be as much a six times thicker than the epidermis covering the general body surface. Thick skin can be found on the palms of the hands and on the soles of the feet. Thin skin covers most of the body. In a sample of thin skin, only 4 layers are present because stratum lucidum is typically absent.

10. Describe wrinkles? Stretch marks? Lines of cleavage.

Wrinkles- Reduced thickness and flexibility of the dermis. Caused by Age, hormones, and ultraviolet radiation. Stretch Marks- Extensive distortion of the dermis during pregnancy or weight gain. This distortion often exceeds the elastic capabilities of the skin. Skin does not recoil to original size and creases. Lines of Cleavage- Clinically significant for surgery to avoid scaring. Cut parallel to tension line will heal the fastest and have minimal scarring.