ScienceIQ.com

The Color of The Sunset

Color in the form of pigment does not exist in the atmosphere. Instead, the color we see in the sky results from the scattering, refraction, and diffraction of sunlight by particles in the atmosphere, especially small particles such as air molecules. If there were no particles in the atmosphere, then sunlight would travel straight down to the Earth ...

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SunsetColor
Physics

Somewhere Over Which Rainbow?

How many rainbows are there really when we only see one during a rainstorm? The answer isn't as simple as you might think! Rainbows are formed when light enters a water droplet, reflects once inside ... Continue reading

DoubleRainbow
Medicine

When Motherhood Means More than One

These days, twins, triplets, and other multiple births are becoming more common, but how do they happen? Fraternal twins (or triplets, quadruplets, or more) develop when two or more eggs are ... Continue reading

MotherhoodMeansMoreOne
Engineering

A Quick Guide To Gliders

A glider is a special kind of aircraft that has no engine. Paper airplanes are the most obvious example, but gliders come in a wide range of sizes. Toy gliders, made of balsa wood or styrofoam, are an ... Continue reading

AQuickGuideToGliders
Geology

Rock, Mineral, Crystal, or Gemstone?

Rocks and minerals are all around us and used every day, perhaps without us even being aware of them. Besides making up the solid, supporting surface of the earth we live and move upon daily, rocks ... Continue reading

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What Causes Wrinkles?

WhatCausesWrinklesElastin and collagen are proteins in the skin's underlying layers that give it firmness and elasticity. As we age, skin begins to lose its elastin fibers. The fibers start to tangle in disorganized masses as blood vessels shrivel, robbing skin of oxygen and nutrients. Thinning and degeneration of elastin over time cause wrinkles, 'worry' and 'laugh' lines, sagging, and crepey rippled skin. Aging skin also loses collagen at the rate of about one percent each year--and even faster if exposed to sunlight. The loss of collagen causes skin to sag and droop. Gravity, the slackening of muscles, and the loss of collagen all contribute to the sagging, wrinkling skin of advancing age.

After age fifty, the loss of both bone and fat beneath the skin lets the skin sag in the loose folds and wrinkles of old age. As we grow older, a drop in hormone levels causes the skin's outer layer to grow thin, giving that shiny parchment appearance of old age. The amount of moisture in the skin declines, so skin cracks and loses suppleness. The outer skin layer thickens--especially if exposed to the sun--becoming rough and scaly. The rates of making and shedding skin cells slow, and the repair of damaged cells becomes less efficient. Sebaceous glands produce less oil, leaving skin rough and dry. The number of pigment-producing cells declines, causing skin to tan poorly and freckle easily. Patches of brown, called 'liver spots' or 'age spots,' appear often on face, neck, or hands. Cancers of the skin become more likely.

Visible changes at the surface are accompanied by changes in the skin's deeper layers. There, blood vessels decline in number, slowing circulation and increasing sensitivity to heat and cold. The amount of collagen decreases and its structure changes, so the skin tears easily. Loss of collagen support for blood vessels means skin bruises more easily and wounds heal more slowly. As great as these changes are, many experts think they are not so much a result of aging as they are consequences of exposure to the sun. They say the best way to maintain youthful skin is to stay out of the sun.