Physics of Color
This term refers to the distance traveled over the course of one oscillation in an electromagnetic wave.
What is wavelength?
This pigment, produced by melanocytes, is primarily responsible for human skin coloration.
What is eumelanin?
This hair color results when melanocytes are no longer present in hair follicles, often increasing with age.
What is white (or gray) hair?
Tibetans developed this enhanced ability, which allows them to temporarily produce more melanin in response to UV exposure.
What is tanning?
This gene shows strong signals of positive selection in Tibetans, helping them adapt to high UV radiation at high altitudes.
What is GNPAT?
These molecules in plants and animals reflect and absorb specific wavelengths of light, producing visible color.
What are pigments?
The primary function of melanin in the skin is to shield this part of the cell from harmful UV radiation.
What is the nucleus?
This type of melanin, alongside eumelanin, contributes to red hair and freckles in humans.
What is pheomelanin?
A higher value of M indicates this trait in skin color among the studied populations.
What is darker skin?
The altitude gradient of this plateau is where Tibetans have developed genetic adaptations to extreme UV radiation.
What is the Qinghai-Tibetan Plateau?
Objects that appear black absorb all wavelengths of visible light. This is why black objects exhibit this physical effect when exposed to sunlight.
What is increased heat absorption?
This vitamin, synthesized by the skin when exposed to UV rays, plays an essential role in bone growth and immune system function.
What is vitamin D?
The depletion of these stem cells, which replenish pigment-producing cells in hair follicles, leads to the gradual loss of hair color over time.
What are melanocyte stem cells?
This type of adaptation refers to Tibetans’ ability to have both a darker baseline skin color and improved tanning ability to cope with UV radiation.
What is two-level genetic adaptation?
The Tibetan population at this altitude shows the highest UV irradiance measured at 15.37 W/m².
What is 4,352 m (Rikaze)?
This form of electromagnetic radiation is shorter in wavelength than visible light and can ionize atoms by knocking off electrons, making it potentially harmful to biological tissues.
What is ultraviolet (UV) radiation?
This hypothesis explains the evolution of human skin pigmentation to be lighter as a way to maintain levels of a certain beneficial element in our body.
What is the folate-vitamin D hypothesis?
This gene, involved in melanocyte development, has a variant in its regulatory region that leads to blonde hair in northern Europe by reducing its expression in hair follicles.
What is KITLG?
The study found that the average melanin index of Tibetans living at higher altitudes showed a significant increase compared to lower altitude populations, indicating enhanced pigmentation adaptation. This M value difference was measured for which exposed skin area?
What is the hand?
An enhancer mutation in this intron of the GNPAT gene is enriched in Tibetans, contributing to darker skin and improved UV protection.
What is intron 2?
Responsible for the blue color in mandrills and some feathers, this phenomenon involves the refraction of light off structural components rather than pigmentation.
What is structural coloration?
This gene, known for its association with both eye color and skin pigmentation, was selected for in populations in eastern Eurasia and the Americas during the Last Glacial Maximum.
What is OCA2?
The mutation of this gene leads to production of pheomelanin instead of eumelanin and results in the appearance of red hair.
What is MC1R?
Tibetans exhibit this type of skin color that indicates their ability to produce more melanin in response to UV radiation, helping them cope with high-altitude exposure.
What is facultative skin color?
SPECIAL 500 EASY POINTS!!!
Natural pigment in living tissues.
What is biopigment?