ScienceIQ.com

Proteins Function Through Their Conformation

To produce proteins, cellular structures called ribosomes join together long chains of subunits. A set of 20 different subunits, called amino acids, can be arranged in any order to form a polypeptide that can be thousands of amino acids long. These chains can then loop about each other, or fold, in a variety of ways, but only one of these ways ...

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ProteinConformation
Geology

Who Named The Cloud Types?

Clouds held a particular fascination for a young Englishman named Luke Howard (1773-1864). His father had sent him to grammar school at Burford, a village to the west of London. But Luke was more ... Continue reading

WhoNamedTheCloudTypes
Astronomy

Large Asteroid Zooms Safely Past Earth

A mountain-sized asteroid made its closest approach to Earth at 9:35 a.m. Eastern Time on Wednesday, Sept. 29, 2004. Although asteroid 4179 Toutatis came no closer than four times the distance between ... Continue reading

LargeAsteroidZoomsPastEarth
Engineering

Hollywood To The Rescue

Sixty years ago, World War II was driving many advances in the sciences; a surprising number of these developments have evolved to impact our lives today. At the beginning of the war, scientists and ... Continue reading

HollywoodRescue
Biology

Tea Time!

Did you know that a disease of coffee plantations made the British tea drinkers? In the 1700s Britain had many coffeehouses that served as popular social gathering places to discuss current events and ... Continue reading

TeaTime

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.