Transcript Life Span Changes

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?
6.7 Aging
2.1 Atoms,
Ions, and Skin Cancer
and Molecules
1. What is the most common type of skin
cancer? Who is most likely to develop this
cancer?
Send someone up to get
notebook check—
DUE FRIDAY
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 Changes
Epidermis
• 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 Changes
Dermis
•
•
•
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 Changes
Accessory 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
p. 52
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
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p. 52
Skin Cancer
(definition)
Carcinoma
Melanoma
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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
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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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