Chapter 14, Lesson 1

Guided Reading Activity 50

Healthy Skin, Hair and Nails

1a. Complete the following questions about the skin.

Your skin produces perspiration in order to __.

To help keep your body cool.

1b. Complete the following questions about the skin.

Skin is the main organ of the –system.

Integumentary system

1c. Complete the following questions about the skin.

In addition to skin, the integumentary system includes --,--, and --.

Hair,

nails

and glands

found in your skin

1d. Complete the following questions about the skin.

Your skin serves as a physical barrier between – and --.

the outside world and your internal organs

1e. Complete the following questions about the skin.

Your skin is the first line of defense against --.

Pathogens entering the body.

2. Name and define two layers of the skin.

• Epidermis:– Outer thinner layer of

the skin.– Composed of living

and dead cells.

• Dermis:– Thicker layer of skin

beneath the epidermis

– Made up of connective tissue, blood vessels and nerves.

3. Describe the purpose of the substances listed below, all of which

are produced in the epidermis.a.Keratin• Toughens nails

b.Lipids• Make skin waterproof• Helps keep balance between water and

electrolytes.

c.Melanin• Gives skin color• As well as hair, iris of the eyes.

Describe the function of the structures listed below, all of

which are found in the dermis.

Connective tissue• Gives skin its elastic qualities.

Describe the function of the structures listed below, all of which are found in the dermis.

Sebaceous glands– Produce sebum– An oily substance

which helps keep the skin and hair from drying out.

Describe the function of the structures

listed below, all of which are found in the

dermis.

Blood vessels– Supply cells with

oxygenated blood and nutrients

– Facilitates the removal of cellular wastes.

Describe the function of the structures listed

below, all of which are found in the dermis.

Sweat glands– Secrete perspiration– Involved in temperature

regulation– Body heat is lost as

sweat evaporates

Describe the function of the

structures listed below, all of which

are found in the dermis.

Nerve cells• Act as receptors

and enable you to feel sensations

• Tactile corpuscles sense heat, pressure, pain, cold

5. Explain how blood vessels in the dermis and sweat glands work to

regulate body temperature.

• Blood vessels in the skin dilate when body temperature rises allowing heat to escape.

• Blood vessels contract when body temperature drops to hold the heat.

6a. Explain how ultraviolet radiation is related to each of the following:

Melanin production is increased when skin is exposed to UV radiation.

Sunburns

Light skinned people with few melanocytes will burn.

Suntan• Darker skinned people with more

melanocytes will tan.

6b. Explain how ultraviolet radiation is related to Cancer

UV rays damage the genetic material in skin cells and cause a mutation.

These changes can result in the development of cancer.

Cancer in the melanocytes is called melanoma.

6c. Explain how ultraviolet radiation is related to Wrinkles:

UV radiation breaks down the elastic fibers that support your skin and allow it to be flexible.

Resulting in wrinkled or hard and leathery skin.

7. What are two steps you can take to protect your skin from the damaging rays of the sun.

• Always wear sunscreen on exposed areas of skin.

• Wear protective clothing.

8. What are the health risks of body

piercing and tattooing?

• Both result in physical barrier of the skin being broken.

• Increases probability of bacteria entering the body.

• Tattooing has additional with nonsterile needles being used.

9. Why is monitoring the appearance of moles important?

• May develop into melanoma.

• Monitoring moles is essential to early detection.

• Maureen Regan

10a. What are four early warning signs of melanoma?

A = Asymmetry: melanoma lesions are typically asymmetrical, whereas benign moles are typically round and symmetrical.

10b. What are four early warning signs of melanoma?

B = Border: melanoma lesions frequently have uneven or irregular borders (i.e., ragged or notched edges), whereas benign moles have smooth, even borders.

10c. What are four early warning signs of melanoma?

C = Color: melanoma lesions often contain multiple shades of brown or black, whereas benign benign moles are usually a single shade of brown.

10d. What are four early warning signs of melanoma?

D = Diameter: early melanoma lesions are often more than 6 mm in diameter, whereas

benignbenign moles are usually less than 6 mm in diameter.

11. Complete the following sentences about your hair.

a. A hair follicle is --.• Structure that surrounds the root of a

hair

b. Hair helps protect the skin from exposure to –• UV radiation, dust

c. Hair reduces the amount of – lost through the skin of the scalp.• heat

12. What is dandruff?

• The scalp becomes to dry

• Dead skin cells are shed as sticky white flakes.

13. Answer these questions about head lice.

a.What are head lice?• Tiny parasitic

insects

• Live in the human scalp

13. Answer these questions about head lice.

b. How are head lice transmitted?

• Head to head contact c. How can head lice be

eliminated?Washing hair with

medicated shampoo.Washing sheets,

pillowcases, combs, hats.

Other Skin Problems:

What is Acne?

• Hormones cause the oil glands to enlarge and produce excess sebum, which provides an ideal place for bacteria to grow.

What are Boils?

• They are a serious infection and the bacteria in them could spread.

What are Warts?

–Small growths caused by a virus.

What is Psoriasis?

• Psoriasis– An ailment in which red

patches appear on the skin, followed by the skin turning white and flaking off.

What is Vitiligo?

• A whitish or pinkish patch on the skin, caused by a localized lack of melanin.