Sponge: Set up Cornell Notes on pg. 53

Topic: 6.7 Aging and Skin Cancer

Essential Questions:

1. What is the most common type of skin cancer? Who is most likely to develop this cancer?

2.1 Atoms, Ions, and Molecules

1. What is the most common type of skin cancer? Who is most likely to develop this cancer?

6.7 Aging and Skin Cancer

Send someone up to get notebook check—DUE FRIDAY

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Life Span Changes

Why are we more aware of aging-related changes in skin than in other organ systems?• We can easily see them• Aging affects appearance

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Life Span Changes

Aging skin affects appearance, temperature regulation, and vitamin D activation

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Life Span ChangesEpidermis• Thins• Cell cycle slows• Epidermal cells grow larger and irregular in shape

• Skin may appear scaly• Age spots or liver spots appear/grow

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Life Span ChangesDermis• Dermis is reduced as the

production of collagen and elastin slows• Loss of fat from

subcutaneous layers• Sagging and wrinkling of the

skin• Delay of wound healing• Decrease of oil production

• Dry skin

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Life Span ChangesAccessory Structures:• Slowed melanin production as

follicle becomes transparent• Grays or whitens hair

• Hair follicles decrease in #• Hair growth slows• Hair thins• Males may develop

baldness• Diminished blood supply to

nails impairs growth• Dull and hardened

• Number of pain/pressure receptors decline• Less sensitive

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Life Span Changes

Accessory Structures:• Ability to control temperature

falters as sweat gland and hair follicle shrink and # decreases• Ability to shiver declines• Less able to tolerate heat/cold

• Fewer blood vessels underlying the skin• May appear pale

• Vitamin D production goes down• Loss of ability to maintain

bone structure• Must take vitamins

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Skin Cancer

Skin Cancer begins when ultra violet radiation mutates the DNA of a skin cell

• Usually arises from non-pigmented epithelial cells within the deep layer of the epidermis OR from pigmented melanocytes

p. 52

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p. 52 Skin Cancer

MelanomaCarcinoma

(definition)

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• Cutaneous carcinomas are skin cancers originating from the epithelial cells• Most common type of skin cancer• Occur most freq. in light-skinned people over 40 yrs old• Usually appear in people who are regularly exposed to

sunlight

2 types:• Basal cell carcinoma• Squamous cell carcinoma

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• Cutaneous Melanomas arise from the melanocytes• Seems to be caused by short, intermittent exposure to

high-intensity sunlight• Appear most often in the skin of the trunk, back, and

on limbs

Clinical Application 6.1 Skin Cancer

• Read Clinical App 6.1• Answer the Questions

– HIGHLIGHT the answers in the reading (as evidence)

• Read A Tan is not a Sign of Health– HIGHLIGHT important info

• Work on notebook- due Friday (Eqs/CN?)

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