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Integumentary System . Chapter 6 Section 2. Skin Color. Due largely to melanin Mostly determined by genetics Blood can affect skin color:. Well oxygenated blood = pinkish skin. Poorly oxygenated blood = bluish skin. Skin Color. A diet high in yellow vegetables = yellow-orange skin .
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Integumentary System Chapter 6 Section 2
Skin Color • Due largely to melanin • Mostly determined by genetics • Blood can affect skin color: • Well oxygenated blood = pinkish skin • Poorly oxygenated blood = bluish skin
Skin Color • A diet high in yellow vegetables = yellow-orange skin
Skin Color • Biochemical imbalances may affect skin color • Ex: jaundice
Skin Types • How would you describe your skin type? • What do you do to protect your skin? Why is that important? • What factors influence skin color? • How does your skin compare with that of other family members? • What geographical regions are your ancestors from? • How do the skin types differ? • What similarities do they have? • What can you conclude about these skin-type groups?
Nails • Protective coverings on ends of fingers and toes • Consists of nail plate over a nail bed • New cells are created at the lunula
Did you know?? The thumbnail grows the slowest, the middle nail grows the fastest!
Hair Follicles • Contains hair root • Hair is made of dead epidermal cells • Hair color is determined by genes and melanin
Turn to p. 112 in the text book • Read the selection and answer the following questions in your composition notebook: • What happens to many of our hair follicles after birth? • We have as many hair follicles per square inch as what animal? • About how many hair follicles form on an adult human? • In what month of prenatal development do all hair follicles form in humans? • Why might other mammals, such as whales and manatees, not have hair? • What is the lanugo? • What advantage would having dense hair on the top of the head have? • What is the parasite-reduction hypothesis?